Содержание
- 4.1. Overview of MySQL Programs
- 4.2. Using MySQL Programs
- 4.3. MySQL Server and Server-Startup Programs
- 4.4. MySQL Installation-Related Programs
- 4.4.1. comp_err — Compile MySQL Error Message File
- 4.4.2. mysqlbug — Generate Bug Report
- 4.4.3. mysql_install_db — Initialize MySQL Data Directory
- 4.4.4. mysql_plugin — Configure MySQL Server Plugins
- 4.4.5. mysql_secure_installation — Improve MySQL Installation Security
- 4.4.6. mysql_tzinfo_to_sql — Load the Time Zone Tables
- 4.4.7. mysql_upgrade — Check Tables for MySQL Upgrade
- 4.5. MySQL Client Programs
- 4.5.1. mysql — The MySQL Command-Line Tool
- 4.5.2. mysqladmin — Client for Administering a MySQL Server
- 4.5.3. mysqlcheck — A Table Maintenance Program
- 4.5.4. mysqldump — A Database Backup Program
- 4.5.5. mysqlimport — A Data Import Program
- 4.5.6. mysqlshow — Display Database, Table, and Column Information
- 4.5.7. mysqlslap — Load Emulation Client
- 4.6. MySQL Administrative and Utility Programs
- 4.6.1. innochecksum — Offline InnoDB File Checksum Utility
- 4.6.2. myisam_ftdump — Display Full-Text Index information
- 4.6.3. myisamchk — MyISAM Table-Maintenance Utility
- 4.6.4. myisamlog — Display MyISAM Log File Contents
- 4.6.5. myisampack — Generate Compressed, Read-Only MyISAM Tables
- 4.6.6. mysqlaccess — Client for Checking Access Privileges
- 4.6.7. mysqlbinlog — Utility for Processing Binary Log Files
- 4.6.8. mysqldumpslow — Summarize Slow Query Log Files
- 4.6.9. mysqlhotcopy — A Database Backup Program
- 4.6.10. mysql_convert_table_format — Convert Tables to Use a Given Storage Engine
- 4.6.11. mysql_find_rows — Extract SQL Statements from Files
- 4.6.12. mysql_fix_extensions — Normalize Table File Name Extensions
- 4.6.13. mysql_setpermission — Interactively Set Permissions in Grant Tables
- 4.6.14. mysql_waitpid — Kill Process and Wait for Its Termination
- 4.6.15. mysql_zap — Kill Processes That Match a Pattern
- 4.7. MySQL Program Development Utilities
- 4.8. Miscellaneous Programs
This chapter provides a brief overview of the MySQL command-line programs provided by Oracle Corporation. It also discusses the general syntax for specifying options when you run these programs. Most programs have options that are specific to their own operation, but the option syntax is similar for all of them. Finally, the chapter provides more detailed descriptions of individual programs, including which options they recognize.
There are many different programs in a MySQL installation. This section provides a brief overview of them. Later sections provide a more detailed description of each one, with the exception of MySQL Cluster programs. Each program's description indicates its invocation syntax and the options that it supports. Глава 16, MySQL Cluster NDB 7.2, describes programs specific to MySQL Cluster.
Most MySQL distributions include all of these programs, except for those programs that are platform-specific. (For example, the server startup scripts are not used on Windows.) The exception is that RPM distributions are more specialized. There is one RPM for the server, another for client programs, and so forth. If you appear to be missing one or more programs, see Глава 2, Installing and Upgrading MySQL, for information on types of distributions and what they contain. It may be that you have a distribution that does not include all programs and you need to install an additional package.
Each MySQL program takes many different options. Most programs
provide a --help
option that you can use to get a
description of the program's different options. For example, try
mysql --help.
You can override default option values for MySQL programs by specifying options on the command line or in an option file. See Section 4.2, “Using MySQL Programs”, for general information on invoking programs and specifying program options.
The MySQL server, mysqld, is the main program that does most of the work in a MySQL installation. The server is accompanied by several related scripts that assist you in starting and stopping the server:
The SQL daemon (that is, the MySQL server). To use client programs, mysqld must be running, because clients gain access to databases by connecting to the server. See Section 4.3.1, “mysqld — The MySQL Server”.
A server startup script. mysqld_safe attempts to start mysqld. See Section 4.3.2, “mysqld_safe — MySQL Server Startup Script”.
A server startup script. This script is used on systems that use System V-style run directories containing scripts that start system services for particular run levels. It invokes mysqld_safe to start the MySQL server. See Section 4.3.3, “mysql.server — MySQL Server Startup Script”.
A server startup script that can start or stop multiple servers installed on the system. See Section 4.3.4, “mysqld_multi — Manage Multiple MySQL Servers”.
Several programs perform setup operations during MySQL installation or upgrading:
This program is used during the MySQL build/installation process. It compiles error message files from the error source files. See Section 4.4.1, “comp_err — Compile MySQL Error Message File”.
This script creates the MySQL database and initializes the grant tables with default privileges. It is usually executed only once, when first installing MySQL on a system. See Section 4.4.3, “mysql_install_db — Initialize MySQL Data Directory”, Section 2.10.1, “Unix Postinstallation Procedures”, and Section 4.4.3, “mysql_install_db — Initialize MySQL Data Directory”.
This program configures MySQL server plugins. See Section 4.4.4, “mysql_plugin — Configure MySQL Server Plugins”.
This program enables you to improve the security of your MySQL installation. SQL. See Section 4.4.5, “mysql_secure_installation — Improve MySQL Installation Security”.
This program loads the time zone tables in the
mysql
database using the contents of the host system zoneinfo database (the set of files describing time zones). SQL. See Section 4.4.6, “mysql_tzinfo_to_sql — Load the Time Zone Tables”.This program is used after a MySQL upgrade operation. It checks tables for incompatibilities and repairs them if necessary, and updates the grant tables with any changes that have been made in newer versions of MySQL. See Section 4.4.7, “mysql_upgrade — Check Tables for MySQL Upgrade”.
MySQL client programs that connect to the MySQL server:
The command-line tool for interactively entering SQL statements or executing them from a file in batch mode. See Section 4.5.1, “mysql — The MySQL Command-Line Tool”.
A client that performs administrative operations, such as creating or dropping databases, reloading the grant tables, flushing tables to disk, and reopening log files. mysqladmin can also be used to retrieve version, process, and status information from the server. See Section 4.5.2, “mysqladmin — Client for Administering a MySQL Server”.
A table-maintenance client that checks, repairs, analyzes, and optimizes tables. See Section 4.5.3, “mysqlcheck — A Table Maintenance Program”.
A client that dumps a MySQL database into a file as SQL, text, or XML. See Section 4.5.4, “mysqldump — A Database Backup Program”.
A client that imports text files into their respective tables using
LOAD DATA INFILE
. See Section 4.5.5, “mysqlimport — A Data Import Program”.A client that displays information about databases, tables, columns, and indexes. See Section 4.5.6, “mysqlshow — Display Database, Table, and Column Information”.
A client that is designed to emulate client load for a MySQL server and report the timing of each stage. It works as if multiple clients are accessing the server. See Section 4.5.7, “mysqlslap — Load Emulation Client”.
MySQL administrative and utility programs:
An offline
InnoDB
offline file checksum utility. See Section 4.6.1, “innochecksum — Offline InnoDB File Checksum Utility”.A utility that displays information about full-text indexes in
MyISAM
tables. See Section 4.6.2, “myisam_ftdump — Display Full-Text Index information”.A utility to describe, check, optimize, and repair
MyISAM
tables. See Section 4.6.3, “myisamchk — MyISAM Table-Maintenance Utility”.myisamlog, isamlog
A utility that processes the contents of a
MyISAM
log file. See Section 4.6.4, “myisamlog — Display MyISAM Log File Contents”.A utility that compresses
MyISAM
tables to produce smaller read-only tables. See Section 4.6.5, “myisampack — Generate Compressed, Read-Only MyISAM Tables”.A script that checks the access privileges for a host name, user name, and database combination. See Section 4.6.6, “mysqlaccess — Client for Checking Access Privileges”.
A utility for reading statements from a binary log. The log of executed statements contained in the binary log files can be used to help recover from a crash. See Section 4.6.7, “mysqlbinlog — Utility for Processing Binary Log Files”.
A utility to read and summarize the contents of a slow query log. See Section 4.6.8, “mysqldumpslow — Summarize Slow Query Log Files”.
A utility that quickly makes backups of
MyISAM
tables while the server is running. See Section 4.6.9, “mysqlhotcopy — A Database Backup Program”.A utility that converts tables in a database to use a given storage engine. See Section 4.6.10, “mysql_convert_table_format — Convert Tables to Use a Given Storage Engine”.
A utility that reads files containing SQL statements (such as update logs) and extracts statements that match a given regular expression. See Section 4.6.11, “mysql_find_rows — Extract SQL Statements from Files”.
A utility that converts the extensions for
MyISAM
table files to lowercase. This can be useful after transferring the files from a system with case-insensitive file names to a system with case-sensitive file names. See Section 4.6.12, “mysql_fix_extensions — Normalize Table File Name Extensions”.A utility for interactively setting permissions in the MySQL grant tables. See Section 4.6.13, “mysql_setpermission — Interactively Set Permissions in Grant Tables”.
A utility that kills the process with a given process ID. See Section 4.6.14, “mysql_waitpid — Kill Process and Wait for Its Termination”.
A utility that kills processes that match a pattern. See Section 4.6.15, “mysql_zap — Kill Processes That Match a Pattern”.
MySQL program-development utilities:
A shell script that converts
mSQL
programs to MySQL. It doesn't handle every case, but it gives a good start when converting. See Section 4.7.1, “msql2mysql — Convert mSQL Programs for Use with MySQL”.A shell script that produces the option values needed when compiling MySQL programs. See Section 4.7.2, “mysql_config — Get Compile Options for Compiling Clients”.
A utility that shows which options are present in option groups of option files. See Section 4.7.3, “my_print_defaults — Display Options from Option Files”.
A utility program that resolves a numeric stack trace dump to symbols. See Section 4.7.4, “resolve_stack_dump — Resolve Numeric Stack Trace Dump to Symbols”.
Miscellaneous utilities:
A utility that displays the meaning of system or MySQL error codes. See Section 4.8.1, “perror — Explain Error Codes”.
A utility program that performs string replacement in the input text. See Section 4.8.2, “replace — A String-Replacement Utility”.
A utility program that resolves a host name to an IP address or vice versa. See Section 4.8.3, “resolveip — Resolve Host name to IP Address or Vice Versa”.
Oracle Corporation also provides several GUI tools for administering and otherwise working with MySQL Server:
MySQL Workbench: This is the latest graphical tool for working with MySQL databases.
MySQL Administrator: This tool is used for administering MySQL servers, databases, tables, and user accounts.
MySQL Query Browser: This graphical tool is used for creating, executing, and optimizing queries on MySQL databases.
MySQL Migration Toolkit: This tool helps you migrate schemas and data from other relational database management systems for use with MySQL.
These GUI programs are available at http://dev.mysql.com/downloads/. Each has its own manual that you can access at http://dev.mysql.com/doc/.
MySQL client programs that communicate with the server using the MySQL client/server library use the following environment variables.
Environment Variable | Meaning |
---|---|
MYSQL_UNIX_PORT | The default Unix socket file; used for connections to
localhost |
MYSQL_TCP_PORT | The default port number; used for TCP/IP connections |
MYSQL_PWD | The default password |
MYSQL_DEBUG | Debug trace options when debugging |
TMPDIR | The directory where temporary tables and files are created |
For a full list of environment variables used by MySQL programs, see Section 2.12, “Environment Variables”.
Use of MYSQL_PWD
is insecure. See
Section 5.3.2.2, “End-User Guidelines for Password Security”.
To invoke a MySQL program from the command line (that is, from
your shell or command prompt), enter the program name followed by
any options or other arguments needed to instruct the program what
you want it to do. The following commands show some sample program
invocations. “shell>
”
represents the prompt for your command interpreter; it is not part
of what you type. The particular prompt you see depends on your
command interpreter. Typical prompts are $
for
sh or bash,
%
for csh or
tcsh, and C:\>
for the
Windows command.com or
cmd.exe command interpreters.
shell>mysql --user=root test
shell>mysqladmin extended-status variables
shell>mysqlshow --help
shell>mysqldump -u root personnel
Arguments that begin with a single or double dash
(“-
”,
“--
”) specify program options.
Options typically indicate the type of connection a program should
make to the server or affect its operational mode. Option syntax
is described in Section 4.2.3, “Specifying Program Options”.
Nonoption arguments (arguments with no leading dash) provide
additional information to the program. For example, the
mysql program interprets the first nonoption
argument as a database name, so the command mysql
--user=root test
indicates that you want to use the
test
database.
Later sections that describe individual programs indicate which options a program supports and describe the meaning of any additional nonoption arguments.
Some options are common to a number of programs. The most
frequently used of these are the
--host
(or -h
),
--user
(or -u
),
and --password
(or
-p
) options that specify connection parameters.
They indicate the host where the MySQL server is running, and the
user name and password of your MySQL account. All MySQL client
programs understand these options; they enable you to specify
which server to connect to and the account to use on that server.
Other connection options are
--port
(or -P
) to
specify a TCP/IP port number and
--socket
(or -S
)
to specify a Unix socket file on Unix (or named pipe name on
Windows). For more information on options that specify connection
options, see Section 4.2.2, “Connecting to the MySQL Server”.
You may find it necessary to invoke MySQL programs using the path
name to the bin
directory in which they are
installed. This is likely to be the case if you get a
“program not found” error whenever you attempt to run
a MySQL program from any directory other than the
bin
directory. To make it more convenient to
use MySQL, you can add the path name of the
bin
directory to your PATH
environment variable setting. That enables you to run a program by
typing only its name, not its entire path name. For example, if
mysql is installed in
/usr/local/mysql/bin
, you can run the program
by invoking it as mysql, and it is not
necessary to invoke it as
/usr/local/mysql/bin/mysql.
Consult the documentation for your command interpreter for
instructions on setting your PATH
variable. The
syntax for setting environment variables is interpreter-specific.
(Some information is given in
Section 4.2.4, “Setting Environment Variables”.) After modifying
your PATH
setting, open a new console window on
Windows or log in again on Unix so that the setting goes into
effect.
For a client program to be able to connect to the MySQL server, it must use the proper connection parameters, such as the name of the host where the server is running and the user name and password of your MySQL account. Each connection parameter has a default value, but you can override them as necessary using program options specified either on the command line or in an option file.
The examples here use the mysql client program, but the principles apply to other clients such as mysqldump, mysqladmin, or mysqlshow.
This command invokes mysql without specifying any connection parameters explicitly:
shell> mysql
Because there are no parameter options, the default values apply:
The default host name is
localhost
. On Unix, this has a special meaning, as described later.The default user name is
ODBC
on Windows or your Unix login name on Unix.No password is sent if neither
-p
nor--password
is given.For mysql, the first nonoption argument is taken as the name of the default database. If there is no such option, mysql does not select a default database.
To specify the host name and user name explicitly, as well as a password, supply appropriate options on the command line:
shell>mysql --host=localhost --user=myname --password=mypass mydb
shell>mysql -h localhost -u myname -pmypass mydb
For password options, the password value is optional:
If you use a
-p
or--password
option and specify the password value, there must be no space between-p
or--password=
and the password following it.If you use a
-p
or--password
option but do not specify the password value, the client program prompts you to enter the password. The password is not displayed as you enter it. This is more secure than giving the password on the command line. Other users on your system may be able to see a password specified on the command line by executing a command such as ps auxw. See Section 5.3.2.2, “End-User Guidelines for Password Security”.
As just mentioned, including the password value on the command
line can be a security risk. To avoid this problem, specify the
--password
or -p
option without
any following password value:
shell>mysql --host=localhost --user=myname --password mydb
shell>mysql -h localhost -u myname -p mydb
When the password option has no password value, the client program
prints a prompt and waits for you to enter the password. (In these
examples, mydb
is not
interpreted as a password because it is separated from the
preceding password option by a space.)
On some systems, the library routine that MySQL uses to prompt for a password automatically limits the password to eight characters. That is a problem with the system library, not with MySQL. Internally, MySQL does not have any limit for the length of the password. To work around the problem, change your MySQL password to a value that is eight or fewer characters long, or put your password in an option file.
On Unix, MySQL programs treat the host name
localhost
specially, in a way that is likely
different from what you expect compared to other network-based
programs. For connections to localhost
, MySQL
programs attempt to connect to the local server by using a Unix
socket file. This occurs even if a
--port
or -P
option is given to specify a port number. To ensure that the
client makes a TCP/IP connection to the local server, use
--host
or -h
to
specify a host name value of 127.0.0.1
, or the
IP address or name of the local server. You can also specify the
connection protocol explicitly, even for
localhost
, by using the
--protocol=TCP
option. For
example:
shell>mysql --host=127.0.0.1
shell>mysql --protocol=TCP
The --protocol
option enables you
to establish a particular type of connection even when the other
options would normally default to some other protocol.
On Windows, you can force a MySQL client to use a named-pipe
connection by specifying the
--pipe
or
--protocol=PIPE
option, or by
specifying .
(period) as the host name. If
named-pipe connections are not enabled, an error occurs. Use the
--socket
option to specify the
name of the pipe if you do not want to use the default pipe name.
Connections to remote servers always use TCP/IP. This command
connects to the server running on
remote.example.com
using the default port
number (3306):
shell> mysql --host=remote.example.com
To specify a port number explicitly, use the
--port
or -P
option:
shell> mysql --host=remote.example.com --port=13306
You can specify a port number for connections to a local server,
too. However, as indicated previously, connections to
localhost
on Unix will use a socket file by
default. You will need to force a TCP/IP connection as already
described or any option that specifies a port number will be
ignored.
For this command, the program uses a socket file on Unix and the
--port
option is ignored:
shell> mysql --port=13306 --host=localhost
To cause the port number to be used, invoke the program in either of these ways:
shell>mysql --port=13306 --host=127.0.0.1
shell>mysql --port=13306 --protocol=TCP
The following list summarizes the options that can be used to control how client programs connect to the server:
--host=
,host_name
-h
host_name
The host where the server is running. The default value is
localhost
.--password[=
,pass_val
]-p[
pass_val
]The password of the MySQL account. As described earlier, the password value is optional, but if given, there must be no space between
-p
or--password=
and the password following it. The default is to send no password.--pipe
,-W
On Windows, connect to the server using a named pipe. The server must be started with the
--enable-named-pipe
option to enable named-pipe connections.--port=
,port_num
-P
port_num
The port number to use for the connection, for connections made using TCP/IP. The default port number is 3306.
--protocol={TCP|SOCKET|PIPE|MEMORY}
This option explicitly specifies a protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For example, connections on Unix to
localhost
are made using a Unix socket file by default:shell>
mysql --host=localhost
To force a TCP/IP connection to be used instead, specify a
--protocol
option:shell>
mysql --host=localhost --protocol=TCP
The following table shows the permissible
--protocol
option values and indicates the platforms on which each value may be used. The values are not case sensitive.--protocol
ValueConnection Protocol Permissible Operating Systems TCP
TCP/IP connection to local or remote server All SOCKET
Unix socket file connection to local server Unix only PIPE
Named-pipe connection to local or remote server Windows only MEMORY
Shared-memory connection to local server Windows only --shared-memory-base-name=
name
On Windows, the shared-memory name to use, for connections made using shared memory to a local server. The default value is
MYSQL
. The shared-memory name is case sensitive.The server must be started with the
--shared-memory
option to enable shared-memory connections.--socket=
,file_name
-S
file_name
On Unix, the name of the Unix socket file to use, for connections made using a named pipe to a local server. The default Unix socket file name is
/tmp/mysql.sock
.On Windows, the name of the named pipe to use, for connections to a local server. The default Windows pipe name is
MySQL
. The pipe name is not case sensitive.The server must be started with the
--enable-named-pipe
option to enable named-pipe connections.Options that begin with
--ssl
are used for establishing a secure connection to the server using SSL, if the server is configured with SSL support. For details, see Section 5.5.8.3, “SSL Command Options”.--user=
,user_name
-u
user_name
The user name of the MySQL account you want to use. The default user name is
ODBC
on Windows or your Unix login name on Unix.
It is possible to specify different default values to be used when you make a connection so that you need not enter them on the command line each time you invoke a client program. This can be done in a couple of ways:
You can specify connection parameters in the
[client]
section of an option file. The relevant section of the file might look like this:[client] host=
host_name
user=user_name
password=your_pass
Section 4.2.3.3, “Using Option Files”, discusses option files further.
You can specify some connection parameters using environment variables. The host can be specified for mysql using
MYSQL_HOST
. The MySQL user name can be specified usingUSER
(this is for Windows only). The password can be specified usingMYSQL_PWD
, although this is insecure; see Section 5.3.2.2, “End-User Guidelines for Password Security”. For a list of variables, see Section 2.12, “Environment Variables”.
There are several ways to specify options for MySQL programs:
List the options on the command line following the program name. This is common for options that apply to a specific invocation of the program.
List the options in an option file that the program reads when it starts. This is common for options that you want the program to use each time it runs.
List the options in environment variables (see Section 4.2.4, “Setting Environment Variables”). This method is useful for options that you want to apply each time the program runs. In practice, option files are used more commonly for this purpose, but Section 5.6.3, “Running Multiple MySQL Instances on Unix”, discusses one situation in which environment variables can be very helpful. It describes a handy technique that uses such variables to specify the TCP/IP port number and Unix socket file for the server and for client programs.
Options are processed in order, so if an option is specified
multiple times, the last occurrence takes precedence. The
following command causes mysql to connect to
the server running on localhost
:
shell> mysql -h example.com -h localhost
If conflicting or related options are given, later options take precedence over earlier options. The following command runs mysql in “no column names” mode:
shell> mysql --column-names --skip-column-names
MySQL programs determine which options are given first by examining environment variables, then by reading option files, and then by checking the command line. This means that environment variables have the lowest precedence and command-line options the highest.
You can take advantage of the way that MySQL programs process options by specifying default option values for a program in an option file. That enables you to avoid typing them each time you run the program while enabling you to override the defaults if necessary by using command-line options.
An option can be specified by writing it in full or as any
unambiguous prefix. For example, the
--compress
option can be given
to mysqldump as --compr
, but
not as --comp
because the latter is ambiguous:
shell> mysqldump --comp
mysqldump: ambiguous option '--comp' (compatible, compress)
Be aware that the use of option prefixes can cause problems in the event that new options are implemented for a program. A prefix that is unambiguous now might become ambiguous in the future.
Program options specified on the command line follow these rules:
Options are given after the command name.
An option argument begins with one dash or two dashes, depending on whether it is a short form or long form of the option name. Many options have both short and long forms. For example,
-?
and--help
are the short and long forms of the option that instructs a MySQL program to display its help message.Option names are case sensitive.
-v
and-V
are both legal and have different meanings. (They are the corresponding short forms of the--verbose
and--version
options.)Some options take a value following the option name. For example,
-h localhost
or--host=localhost
indicate the MySQL server host to a client program. The option value tells the program the name of the host where the MySQL server is running.For a long option that takes a value, separate the option name and the value by an “
=
” sign. For a short option that takes a value, the option value can immediately follow the option letter, or there can be a space between:-hlocalhost
and-h localhost
are equivalent. An exception to this rule is the option for specifying your MySQL password. This option can be given in long form as--password=
or aspass_val
--password
. In the latter case (with no password value given), the program prompts you for the password. The password option also may be given in short form as-p
or aspass_val
-p
. However, for the short form, if the password value is given, it must follow the option letter with no intervening space. The reason for this is that if a space follows the option letter, the program has no way to tell whether a following argument is supposed to be the password value or some other kind of argument. Consequently, the following two commands have two completely different meanings:shell>
mysql -ptest
shell>mysql -p test
The first command instructs mysql to use a password value of
test
, but specifies no default database. The second instructs mysql to prompt for the password value and to usetest
as the default database.Within option names, dash (“
-
”) and underscore (“_
”) may be used interchangeably. For example,--skip-grant-tables
and--skip_grant_tables
are equivalent. (However, the leading dashes cannot be given as underscores.)For options that take a numeric value, the value can be given with a suffix of
K
,M
, orG
(either uppercase or lowercase) to indicate a multiplier of 1024, 10242 or 10243. For example, the following command tells mysqladmin to ping the server 1024 times, sleeping 10 seconds between each ping:mysql>
mysqladmin --count=1K --sleep=10 ping
Option values that contain spaces must be quoted when given on
the command line. For example, the
--execute
(or -e
)
option can be used with mysql to pass SQL
statements to the server. When this option is used,
mysql executes the statements in the option
value and exits. The statements must be enclosed by quotation
marks. For example, you can use the following command to obtain
a list of user accounts:
mysql>mysql -u root -p --execute="SELECT User, Host FROM mysql.user"
Enter password:******
+------+-----------+ | User | Host | +------+-----------+ | | gigan | | root | gigan | | | localhost | | jon | localhost | | root | localhost | +------+-----------+ shell>
Note that the long form
(--execute
) is followed by an
equal sign (=
).
If you wish to use quoted values within a statement, you will either need to escape the inner quotation marks, or use a different type of quotation marks within the statement from those used to quote the statement itself. The capabilities of your command processor dictate your choices for whether you can use single or double quotation marks and the syntax for escaping quote characters. For example, if your command processor supports quoting with single or double quotation marks, you can use double quotation marks around the statement, and single quotation marks for any quoted values within the statement.
Multiple SQL statements may be passed in the option value on the command line, separated by semicolons:
shell>mysql -u root -p -e "SELECT VERSION();SELECT NOW()"
Enter password:******
+-----------------+ | VERSION() | +-----------------+ | 5.1.5-alpha-log | +-----------------+ +---------------------+ | NOW() | +---------------------+ | 2006-01-05 21:19:04 | +---------------------+
Some options are “boolean” and control behavior
that can be turned on or off. For example, the
mysql client supports a
--column-names
option that
determines whether or not to display a row of column names at
the beginning of query results. By default, this option is
enabled. However, you may want to disable it in some instances,
such as when sending the output of mysql into
another program that expects to see only data and not an initial
header line.
To disable column names, you can specify the option using any of these forms:
--disable-column-names --skip-column-names --column-names=0
The --disable
and --skip
prefixes and the =0
suffix all have the same
effect: They turn the option off.
The “enabled” form of the option may be specified in any of these ways:
--column-names --enable-column-names --column-names=1
As of MySQL 5.5.10, the values ON
,
TRUE
, OFF
, and
FALSE
are also recognized for boolean options
(not case sensitive).
If an option is prefixed by --loose
, a program
does not exit with an error if it does not recognize the option,
but instead issues only a warning:
shell> mysql --loose-no-such-option
mysql: WARNING: unknown option '--no-such-option'
The --loose
prefix can be useful when you run
programs from multiple installations of MySQL on the same
machine and list options in an option file, An option that may
not be recognized by all versions of a program can be given
using the --loose
prefix (or
loose
in an option file). Versions of the
program that recognize the option process it normally, and
versions that do not recognize it issue a warning and ignore it.
mysqld enables a limit to be placed on how
large client programs can set dynamic system variables. To do
this, use a --maximum
prefix with the variable
name. For example,
--maximum-query_cache_size=4M
prevents any
client from making the query cache size larger than 4MB.
Most MySQL programs can read startup options from option files (also sometimes called configuration files). Option files provide a convenient way to specify commonly used options so that they need not be entered on the command line each time you run a program. For the MySQL server, MySQL provides a number of preconfigured option files.
To determine whether a program reads option files, invoke it
with the --help
option. (For
mysqld, use
--verbose
and
--help
.) If the program reads
option files, the help message indicates which files it looks
for and which option groups it recognizes.
On Windows, MySQL programs read startup options from the following files, in the specified order (top items are used first).
File Name | Purpose |
---|---|
,
| Global options |
C:\my.ini , C:\my.cnf | Global options |
,
| Global options |
defaults-extra-file | The file specified with
--defaults-extra-file= ,
if any |
WINDIR
represents the location of
your Windows directory. This is commonly
C:\WINDOWS
. You can determine its exact
location from the value of the WINDIR
environment variable using the following command:
C:\> echo %WINDIR%
INSTALLDIR
represents the MySQL
installation directory. This is typically
C:\
where
PROGRAMDIR
\MySQL\MySQL
5.5 ServerPROGRAMDIR
represents the programs
directory (usually Program Files
on
English-language versions of Windows), when MySQL
5.5 has been installed using the installation and
configuration wizards. See
Section 2.3.5.1, “Starting the MySQL Server Instance Configuration Wizard”.
On Unix, Linux and Mac OS X, MySQL programs read startup options from the following files, in the specified order (top items are used first).
File Name | Purpose |
---|---|
/etc/my.cnf | Global options |
/etc/mysql/my.cnf | Global options |
| Global options |
$MYSQL_HOME/my.cnf | Server-specific options |
defaults-extra-file | The file specified with
--defaults-extra-file= ,
if any |
~/.my.cnf | User-specific options |
~
represents the current user's home
directory (the value of $HOME
).
SYSCONFDIR
represents the directory
specified with the SYSCONFDIR
option to CMake when MySQL was built. By
default, this is the etc
directory located
under the compiled-in installation directory.
MYSQL_HOME
is an environment variable
containing the path to the directory in which the
server-specific my.cnf
file resides. If
MYSQL_HOME
is not set and you start the
server using the mysqld_safe program,
mysqld_safe attempts to set
MYSQL_HOME
as follows:
Let
BASEDIR
andDATADIR
represent the path names of the MySQL base directory and data directory, respectively.If there is a
my.cnf
file inDATADIR
but not inBASEDIR
, mysqld_safe setsMYSQL_HOME
toDATADIR
.Otherwise, if
MYSQL_HOME
is not set and there is nomy.cnf
file inDATADIR
, mysqld_safe setsMYSQL_HOME
toBASEDIR
.
In MySQL 5.5, use of
DATADIR
as the location for
my.cnf
is deprecated.
Typically, DATADIR
is
/usr/local/mysql/data
for a binary
installation or /usr/local/var
for a source
installation. Note that this is the data directory location that
was specified at configuration time, not the one specified with
the --datadir
option when
mysqld starts. Use of
--datadir
at runtime has no
effect on where the server looks for option files, because it
looks for them before processing any options.
MySQL looks for option files in the order just described and reads any that exist. If an option file that you want to use does not exist, create it with a plain text editor.
If multiple instances of a given option are found, the last
instance takes precedence. There is one exception: For
mysqld, the first
instance of the --user
option is
used as a security precaution, to prevent a user specified in an
option file from being overridden on the command line.
On Unix platforms, MySQL ignores configuration files that are world-writable. This is intentional as a security measure.
Any long option that may be given on the command line when
running a MySQL program can be given in an option file as well.
To get the list of available options for a program, run it with
the --help
option.
The syntax for specifying options in an option file is similar
to command-line syntax (see
Section 4.2.3.1, “Using Options on the Command Line”). However, in an option
file, you omit the leading two dashes from the option name and
you specify only one option per line. For example,
--quick
and --host=localhost
on the command line should be specified as
quick
and host=localhost
on separate lines in an option file. To specify an option of the
form
--loose-
in
an option file, write it as
opt_name
loose-
.
opt_name
Empty lines in option files are ignored. Nonempty lines can take any of the following forms:
#
,comment
;
comment
Comment lines start with “
#
” or “;
”. A “#
” comment can start in the middle of a line as well.[
group
]group
is the name of the program or group for which you want to set options. After a group line, any option-setting lines apply to the named group until the end of the option file or another group line is given.opt_name
This is equivalent to
--
on the command line.opt_name
opt_name
=value
This is equivalent to
--
on the command line. In an option file, you can have spaces around the “opt_name
=value
=
” character, something that is not true on the command line. You can optionally enclose the value within single quotation marks or double quotation marks, which is useful if the value contains a “#
” comment character.
Leading and trailing spaces are automatically deleted from option names and values.
You can use the escape sequences
“\b
”,
“\t
”,
“\n
”,
“\r
”,
“\\
”, and
“\s
” in option values to
represent the backspace, tab, newline, carriage return,
backslash, and space characters. The escaping rules in option
files are:
If a backslash is followed by a valid escape sequence character, the sequence is converted to the character represented by the sequence. For example, “
\s
” is converted to a space.If a backslash is not followed by a valid escape sequence character, it remains unchanged. For example, “
\S
” is retained as is.
The preceding rules mean that a literal backslash can be given
as “\\
”, or as
“\
” if it is not followed by a
valid escape sequence character.
The rules for escape sequences in option files differ slightly
from the rules for escape sequences in string literals in SQL
statements. In the latter context, if
“x
” is not a value
escape sequence character,
“\
”
becomes “x
x
” rather than
“\
”.
See Section 8.1.1, “String Literals”.
x
The escaping rules for option file values are especially
pertinent for Windows path names, which use
“\
” as a path name separator. A
separator in a Windows path name must be written as
“\\
” if it is followed by an
escape sequence character. It can be written as
“\\
” or
“\
” if it is not. Alternatively,
“/
” may be used in Windows path
names and will be treated as
“\
”. Suppose that you want to
specify a base directory of C:\Program
Files\MySQL\MySQL Server 5.5
in an
option file. This can be done several ways. Some examples:
basedir="C:\Program Files\MySQL\MySQL Server 5.5" basedir="C:\\Program Files\\MySQL\\MySQL Server 5.5" basedir="C:/Program Files/MySQL/MySQL Server 5.5" basedir=C:\\Program\sFiles\\MySQL\\MySQL\sServer\s5.5
If an option group name is the same as a program name, options
in the group apply specifically to that program. For example,
the [mysqld]
and [mysql]
groups apply to the mysqld server and the
mysql client program, respectively.
The [client]
option group is read by all
client programs (but not by
mysqld). This enables you to specify options
that apply to all clients. For example,
[client]
is the perfect group to use to
specify the password that you use to connect to the server. (But
make sure that the option file is readable and writable only by
yourself, so that other people cannot find out your password.)
Be sure not to put an option in the [client]
group unless it is recognized by all client
programs that you use. Programs that do not understand the
option quit after displaying an error message if you try to run
them.
Here is a typical global option file:
[client] port=3306 socket=/tmp/mysql.sock [mysqld] port=3306 socket=/tmp/mysql.sock key_buffer_size=16M max_allowed_packet=8M [mysqldump] quick
The preceding option file uses
syntax for the lines that set the
var_name
=value
key_buffer_size
and
max_allowed_packet
variables.
Here is a typical user option file:
[client] # The following password will be sent to all standard MySQL clients password="my_password" [mysql] no-auto-rehash connect_timeout=2 [mysqlhotcopy] interactive-timeout
If you want to create option groups that should be read by
mysqld servers from a specific MySQL release
series only, you can do this by using groups with names of
[mysqld-5.1]
,
[mysqld-5.5]
, and so forth. The
following group indicates that the --new
option
should be used only by MySQL servers with 5.5.x
version numbers:
[mysqld-5.5] new
It is possible to use !include
directives in
option files to include other option files and
!includedir
to search specific directories
for option files. For example, to include the
/home/mydir/myopt.cnf
file, use the
following directive:
!include /home/mydir/myopt.cnf
To search the /home/mydir
directory and
read option files found there, use this directive:
!includedir /home/mydir
There is no guarantee about the order in which the option files in the directory will be read.
Currently, any files to be found and included using the
!includedir
directive on Unix operating
systems must have file names ending in
.cnf
. On Windows, this directive checks
for files with the .ini
or
.cnf
extension.
Write the contents of an included option file like any other
option file. That is, it should contain groups of options, each
preceded by a
[
line that
indicates the program to which the options apply.
group
]
While an included file is being processed, only those options in
groups that the current program is looking for are used. Other
groups are ignored. Suppose that a my.cnf
file contains this line:
!include /home/mydir/myopt.cnf
And suppose that /home/mydir/myopt.cnf
looks like this:
[mysqladmin] force [mysqld] key_buffer_size=16M
If my.cnf
is processed by
mysqld, only the [mysqld]
group in /home/mydir/myopt.cnf
is used. If
the file is processed by mysqladmin, only the
[mysqladmin]
group is used. If the file is
processed by any other program, no options in
/home/mydir/myopt.cnf
are used.
The !includedir
directive is processed
similarly except that all option files in the named directory
are read.
Most MySQL programs that support option files handle the following options. They affect option-file handling, so they must be given on the command line and not in an option file. To work properly, each of these options must immediately follow the command name, with these exceptions:
--print-defaults
may be used immediately after--defaults-file
or--defaults-extra-file
.On Windows, if the
--defaults-file
and--install
options are given,--install
option must be first. See Section 2.3.6.7, “Starting MySQL as a Windows Service”.
When specifying file names, you should avoid the use of the
“~
” shell metacharacter
because it might not be interpreted as you expect.
--defaults-extra-file=
file_name
Read this option file after the global option file but (on Unix) before the user option file. If the file does not exist or is otherwise inaccessible, the program exits with an error. Before MySQL 5.5.8,
file_name
must be the full path name to the file. As of MySQL 5.5.8, the name is interpreted relative to the current directory if given as a relative path name.Use only the given option file. If the file does not exist or is otherwise inaccessible, the program exits with an error. Before MySQL 5.5.8,
file_name
must be the full path name to the file. As of MySQL 5.5.8, the name is interpreted relative to the current directory if given as a relative path name.If this option is given, the program reads not only its usual option groups, but also groups with the usual names and a suffix of
str
. For example, the mysql client normally reads the[client]
and[mysql]
groups. If the--defaults-group-suffix=_other
option is given, mysql also reads the[client_other]
and[mysql_other]
groups.Do not read any option files. If a program does not start because it is reading unknown options from an option file,
--no-defaults
can be used to prevent the program from reading them.Print the program name and all options that it gets from option files.
MySQL provides a number of preconfigured option files that can
be used as a basis for tuning the MySQL server. Look for files
such as my-small.cnf
,
my-medium.cnf
,
my-large.cnf
, and
my-huge.cnf
, which are sample option
files for small, medium, large, and very large systems. On
Windows, the extension is .ini
rather
than .cnf
.
On Windows, the .ini
or
.cnf
option file extension might not be
displayed.
For a binary distribution, look for the files in or under your
installation directory. If you have a source distribution,
look in the support-files
directory. You
can rename a copy of a sample file and place it in the
appropriate location for use as a base configuration file.
Regarding names and appropriate location, see the general
information provided in Section 4.2.3.3, “Using Option Files”.
Many MySQL programs have internal variables that can be set at
runtime using the
SET
statement. See Section 12.7.4, “SET
Синтаксис”, and
Section 5.1.4, “Using System Variables”.
Most of these program variables also can be set at server
startup by using the same syntax that applies to specifying
program options. For example, mysql has a
max_allowed_packet
variable that controls the
maximum size of its communication buffer. To set the
max_allowed_packet
variable for
mysql to a value of 16MB, use either of the
following commands:
shell>mysql --max_allowed_packet=16777216
shell>mysql --max_allowed_packet=16M
The first command specifies the value in bytes. The second
specifies the value in megabytes. For variables that take a
numeric value, the value can be given with a suffix of
K
, M
, or
G
(either uppercase or lowercase) to indicate
a multiplier of 1024, 10242 or
10243. (For example, when used to set
max_allowed_packet
, the suffixes indicate
units of kilobytes, megabytes, or gigabytes.)
In an option file, variable settings are given without the leading dashes:
[mysql] max_allowed_packet=16777216
Or:
[mysql] max_allowed_packet=16M
If you like, underscores in a variable name can be specified as dashes. The following option groups are equivalent. Both set the size of the server's key buffer to 512MB:
[mysqld] key_buffer_size=512M [mysqld] key-buffer-size=512M
A variable can be specified by writing it in full or as any
unambiguous prefix. For example, the
max_allowed_packet
variable can be set for
mysql as --max_a
, but not as
--max
because the latter is ambiguous:
shell> mysql --max=1000000
mysql: ambiguous option '--max=1000000' (max_allowed_packet, max_join_size)
Be aware that the use of variable prefixes can cause problems in the event that new variables are implemented for a program. A prefix that is unambiguous now might become ambiguous in the future.
Suffixes for specifying a value multiplier can be used when
setting a variable at server startup, but not to set the value
with
SET
at
runtime. On the other hand, with
SET
you
can assign a variable's value using an expression, which is not
true when you set a variable at server startup. For example, the
first of the following lines is legal at server startup, but the
second is not:
shell>mysql --max_allowed_packet=16M
shell>mysql --max_allowed_packet=16*1024*1024
Conversely, the second of the following lines is legal at runtime, but the first is not:
mysql>SET GLOBAL max_allowed_packet=16M;
mysql>SET GLOBAL max_allowed_packet=16*1024*1024;
Before MySQL 4.0.2, the only syntax for setting program
variables was
--set-variable=
(or
option
=value
set-variable=
in option files). Underscores cannot be given as dashes, and
the variable name must be specified in full. This syntax is
deprecated and was removed in MySQL 5.5.3.
option
=value
By convention, long forms of options that assign a value are
written with an equals (=
) sign, like this:
shell> mysql --host=tonfisk --user=jon
For options that require a value (that is, not having a default value), the equal sign is not required, and so the following is also valid:
shell> mysql --host tonfisk --user jon
In both cases, the mysql client attempts to connect to a MySQL server running on the host named “tonfisk” using an account with the user name “jon”.
Due to this behavior, problems can occasionally arise when no
value is provided for an option that expects one. Consider the
following example, where a user connects to a MySQL server
running on host tonfisk
as user
jon
:
shell>mysql --host 85.224.35.45 --user jon
Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 3 Server version: 5.5.22 Source distribution Type 'help;' or '\h' for help. Type '\c' to clear the buffer. mysql>SELECT CURRENT_USER();
+----------------+ | CURRENT_USER() | +----------------+ | jon@% | +----------------+ 1 row in set (0.00 sec)
Omitting the required value for one of these option yields an error, such as the one shown here:
shell> mysql --host 85.224.35.45 --user
mysql: option '--user' requires an argument
In this case, mysql was unable to find a
value following the --user
option because nothing came after it on the command line.
However, if you omit the value for an option that is
not the last option to be used, you obtain
a different error that you may not be expecting:
shell> mysql --host --user jon
ERROR 2005 (HY000): Unknown MySQL server host '--user' (1)
Because mysql assumes that any string
following --host
on the command
line is a host name, --host
--user
is interpreted as
--host=--user
, and the client
attempts to connect to a MySQL server running on a host named
“--user”.
Options having default values always require an equal sign when
assigning a value; failing to do so causes an error. For
example, the MySQL server
--log-error
option has the
default value
,
where host_name
.errhost_name
is the name of the
host on which MySQL is running. Assume that you are running
MySQL on a computer whose host name is “tonfisk”,
and consider the following invocation of
mysqld_safe:
shell> mysqld_safe &
[1] 11699
shell> 080112 12:53:40 mysqld_safe Logging to '/usr/local/mysql/var/tonfisk.err'.
080112 12:53:40 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/var
shell>
After shutting down the server, restart it as follows:
shell> mysqld_safe --log-error &
[1] 11699
shell> 080112 12:53:40 mysqld_safe Logging to '/usr/local/mysql/var/tonfisk.err'.
080112 12:53:40 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/var
shell>
The result is the same, since
--log-error
is not followed
by anything else on the command line, and it supplies its own
default value. (The &
character tells the
operating system to run MySQL in the background; it is ignored
by MySQL itself.) Now suppose that you wish to log errors to a
file named my-errors.err
. You might try
starting the server with --log-error my-errors
,
but this does not have the intended effect, as shown here:
shell> mysqld_safe --log-error my-errors &
[1] 31357
shell> 080111 22:53:31 mysqld_safe Logging to '/usr/local/mysql/var/tonfisk.err'.
080111 22:53:32 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/var
080111 22:53:34 mysqld_safe mysqld from pid file /usr/local/mysql/var/tonfisk.pid ended
[1]+ Done ./mysqld_safe --log-error my-errors
The server attempted to start using
/usr/local/mysql/var/tonfisk.err
as the
error log, but then shut down. Examining the last few lines of
this file shows the reason:
shell> tail /usr/local/mysql/var/tonfisk.err
080111 22:53:32 InnoDB: Started; log sequence number 0 46409
/usr/local/mysql/libexec/mysqld: Too many arguments (first extra is 'my-errors').
Use --verbose --help to get a list of available options
080111 22:53:32 [ERROR] Aborting
080111 22:53:32 InnoDB: Starting shutdown...
080111 22:53:34 InnoDB: Shutdown completed; log sequence number 0 46409
080111 22:53:34 [Note] /usr/local/mysql/libexec/mysqld: Shutdown complete
080111 22:53:34 mysqld_safe mysqld from pid file /usr/local/mysql/var/tonfisk.pid ended
Because the --log-error
option supplies a default value, you must use an equal sign to
assign a different value to it, as shown here:
shell> mysqld_safe --log-error=my-errors &
[1] 31437
shell> 080111 22:54:15 mysqld_safe Logging to '/usr/local/mysql/var/my-errors.err'.
080111 22:54:15 mysqld_safe Starting mysqld daemon with databases from /usr/local/mysql/var
shell>
Now the server has been started successfully, and is logging
errors to the file
/usr/local/mysql/var/my-errors.err
.
Similar issues can arise when specifying option values in option
files. For example, consider a my.cnf
file
that contains the following:
[mysql] host user
When the mysql client reads this file, these
entries are parsed as --host
--user
or
--host=--user
, with the result
shown here:
shell> mysql
ERROR 2005 (HY000): Unknown MySQL server host '--user' (1)
However, in option files, an equal sign is not assumed. Suppose
the my.cnf
file is as shown here:
[mysql] user jon
Trying to start mysql in this case causes a different error:
shell> mysql
mysql: unknown option '--user jon'
A similar error would occur if you were to write host
tonfisk
in the option file rather than
host=tonfisk
. Instead, you must use the equal
sign:
[mysql] user=jon
Now the login attempt succeeds:
shell>mysql
Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 5 Server version: 5.5.22 Source distribution Type 'help;' or '\h' for help. Type '\c' to clear the buffer. mysql>SELECT USER();
+---------------+ | USER() | +---------------+ | jon@localhost | +---------------+ 1 row in set (0.00 sec)
This is not the same behavior as with the command line, where the equals sign is not required:
shell>mysql --user jon --host tonfisk
Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 6 Server version: 5.5.22 Source distribution Type 'help;' or '\h' for help. Type '\c' to clear the buffer. mysql>SELECT USER();
+---------------+ | USER() | +---------------+ | jon@tonfisk | +---------------+ 1 row in set (0.00 sec)
In MySQL 5.5, specifying an option requiring a
value without a value in an option file causes the server to
abort with an error. Suppose that my.cnf
contains the following:
[mysqld] log_error relay_log relay_log_index
This causes the server to fail on startup, as shown here:
shell> mysqld_safe &
090514 09:48:39 mysqld_safe Logging to '/home/jon/bin/mysql-5.5/var/tonfisk.err'.
090514 09:48:39 mysqld_safe Starting mysqld daemon with databases from /home/jon/bin/mysql-5.5/var
090514 09:48:39 mysqld_safe mysqld from pid file /home/jon/bin/mysql-5.5/var/tonfisk.pid ended
The --log-error
option does not
require an argument; however, the
--relay-log
option requires one,
as shown in the error log (which in the absence of a specified
value, defaults to
):
datadir
/hostname
.err
shell> tail -n 3 ../var/tonfisk.err
090514 09:48:39 mysqld_safe Starting mysqld daemon with databases from /home/jon/bin/mysql-5.5/var
090514 9:48:39 [ERROR] /home/jon/bin/mysql-5.5/libexec/mysqld: option '--relay-log' requires an argument
090514 9:48:39 [ERROR] Aborting
This is a change from previous behavior, where the server would
have interpreted the last two lines in the example
my.cnf
file as
--relay-log=relay_log_index
and created a relay
log file using “relay_log_index” as the basename.
(Bug #25192)
Environment variables can be set at the command prompt to affect the current invocation of your command processor, or set permanently to affect future invocations. To set a variable permanently, you can set it in a startup file or by using the interface provided by your system for this purpose. Consult the documentation for your command interpreter for specific details. Section 2.12, “Environment Variables”, lists all environment variables that affect MySQL program operation.
To specify a value for an environment variable, use the syntax
appropriate for your command processor. For example, on Windows,
you can set the USER
variable to specify your
MySQL account name. To do so, use this syntax:
SET USER=your_name
The syntax on Unix depends on your shell. Suppose that you want to
specify the TCP/IP port number using the
MYSQL_TCP_PORT
variable. Typical syntax (such
as for sh, bash
,
zsh, and so on) is as follows:
MYSQL_TCP_PORT=3306 export MYSQL_TCP_PORT
The first command sets the variable, and the
export
command exports the variable to the
shell environment so that its value becomes accessible to MySQL
and other processes.
For csh and tcsh, use setenv to make the shell variable available to the environment:
setenv MYSQL_TCP_PORT 3306
The commands to set environment variables can be executed at your command prompt to take effect immediately, but the settings persist only until you log out. To have the settings take effect each time you log in, use the interface provided by your system or place the appropriate command or commands in a startup file that your command interpreter reads each time it starts.
On Windows, you can set environment variables using the System Control Panel (under Advanced).
On Unix, typical shell startup files are
.bashrc
or .bash_profile
for bash, or .tcshrc
for
tcsh.
Suppose that your MySQL programs are installed in
/usr/local/mysql/bin
and that you want to make
it easy to invoke these programs. To do this, set the value of the
PATH
environment variable to include that
directory. For example, if your shell is bash,
add the following line to your .bashrc
file:
PATH=${PATH}:/usr/local/mysql/bin
bash uses different startup files for login and
nonlogin shells, so you might want to add the setting to
.bashrc
for login shells and to
.bash_profile
for nonlogin shells to make
sure that PATH
is set regardless.
If your shell is tcsh, add the following line
to your .tcshrc
file:
setenv PATH ${PATH}:/usr/local/mysql/bin
If the appropriate startup file does not exist in your home directory, create it with a text editor.
After modifying your PATH
setting, open a new
console window on Windows or log in again on Unix so that the
setting goes into effect.
This section describes mysqld, the MySQL server, and several programs that are used to start the server.
mysqld, also known as MySQL Server, is the main program that does most of the work in a MySQL installation. MySQL Server manages access to the MySQL data directory that contains databases and tables. The data directory is also the default location for other information such as log files and status files.
When MySQL server starts, it listens for network connections from client programs and manages access to databases on behalf of those clients.
The mysqld program has many options that can be specified at startup. For a complete list of options, run this command:
shell> mysqld --verbose --help
MySQL Server also has a set of system variables that affect its operation as it runs. System variables can be set at server startup, and many of them can be changed at runtime to effect dynamic server reconfiguration. MySQL Server also has a set of status variables that provide information about its operation. You can monitor these status variables to access runtime performance characteristics.
For a full description of MySQL Server command options, system variables, and status variables, see Section 5.1, “The MySQL Server”. For information about installing MySQL and setting up the initial configuration, see Глава 2, Installing and Upgrading MySQL.
mysqld_safe is the recommended way to start a mysqld server on Unix. mysqld_safe adds some safety features such as restarting the server when an error occurs and logging runtime information to an error log file. A description of error logging is given later in this section.
mysqld_safe tries to start an executable
named mysqld. To override the default
behavior and specify explicitly the name of the server you want
to run, specify a --mysqld
or --mysqld-version
option
to mysqld_safe. You can also use
--ledir
to indicate the
directory where mysqld_safe should look for
the server.
Many of the options to mysqld_safe are the same as the options to mysqld. See Section 5.1.2, “Server Command Options”.
Options unknown to mysqld_safe are passed to
mysqld if they are specified on the command
line, but ignored if they are specified in the
[mysqld_safe]
group of an option file. See
Section 4.2.3.3, “Using Option Files”.
mysqld_safe reads all options from the
[mysqld]
, [server]
, and
[mysqld_safe]
sections in option files. For
example, if you specify a [mysqld]
section
like this, mysqld_safe will find and use the
--log-error
option:
[mysqld] log-error=error.log
For backward compatibility, mysqld_safe also
reads [safe_mysqld]
sections, although you
should rename such sections to [mysqld_safe]
in MySQL 5.5 installations.
mysqld_safe supports the following options. It also reads option files and supports the options for processing them described at Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
Table 4.1. mysqld_safe
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--basedir=path | basedir | The path to the MySQL installation directory | |||
--core-file-size=size | core-file-size | The size of the core file that mysqld should be able to create | |||
--datadir=path | datadir | The path to the data directory | |||
--defaults-extra-file=path | defaults-extra-file | The name of an option file to be read in addition to the usual option files | |||
--defaults-file=file_name | defaults-file | The name of an option file to be read instead of the usual option files | |||
--help | Display a help message and exit | ||||
--ledir=path | ledir | Use this option to indicate the path name to the directory where the server is located | |||
--log-error=file_name | log-error | Write the error log to the given file | |||
--malloc-lib=[lib-name] | malloc-lib | Alternative malloc library to use for mysqld | |||
--mysqld=prog_name | mysqld | The name of the server program (in the ledir directory) that you want to start | |||
--mysqld-version=suffix | mysqld-version | This option is similar to the --mysqld option, but you specify only the suffix for the server program name | |||
--nice=priority | nice | Use the nice program to set the server's scheduling priority to the given value | |||
--no-defaults | no-defaults | Do not read any option files | |||
--open-files-limit=count | open-files-limit | The number of files that mysqld should be able to open | |||
--pid-file=file_name | pid-file=file_name | The path name of the process ID file | |||
--port=number | port | The port number that the server should use when listening for TCP/IP connections | |||
--skip-kill-mysqld | skip-kill-mysqld | Do not try to kill stray mysqld processes | |||
--skip-syslog | skip-syslog | Do not write error messages to syslog; use error log file | |||
--socket=path | socket | The Unix socket file that the server should use when listening for local connections | |||
--syslog | syslog | Write error messages to syslog | |||
--timezone=timezone | timezone | Set the TZ time zone environment variable to the given option value | |||
--user={user_name|user_id} | user | Run the mysqld server as the user having the name user_name or the numeric user ID user_id |
Display a help message and exit.
The path to the MySQL installation directory.
The size of the core file that mysqld should be able to create. The option value is passed to ulimit -c.
The path to the data directory.
The name of an option file to be read in addition to the usual option files. This must be the first option on the command line if it is used. If the file does not exist or is otherwise inaccessible, the server will exit with an error.
The name of an option file to be read instead of the usual option files. This must be the first option on the command line if it is used.
If mysqld_safe cannot find the server, use this option to indicate the path name to the directory where the server is located.
Write the error log to the given file. See Section 5.2.2, “The Error Log”.
The name of the library to use for memory allocation instead of the system
malloc()
library. Any library can be used by specifying its path name, but there is a shortcut form to enable use of thetcmalloc
library that is shipped with binary MySQL distributions for Linux in MySQL 5.5.The
--malloc-lib
option works by modifying theLD_PRELOAD
environment value to affect dynamic linking to enable the loader to find the memory-allocation library when mysqld runs:If the option is not given, or is given without a value (
--malloc-lib=
),LD_PRELOAD
is not modified and no attempt is made to usetcmalloc
.If the option is given as
--malloc-lib=tcmalloc
, mysqld_safe looks for atcmalloc
library in/usr/lib
and then in the MySQLpkglibdir
location (for example,/usr/local/mysql/lib
or whatever is appropriate). Iftmalloc
is found, its path name is added to the beginning of theLD_PRELOAD
value for mysqld. Iftcmalloc
is not found, mysqld_safe aborts with an error.If the option is given as
--malloc-lib=
, that full path is added to the beginning of the/path/to/some/library
LD_PRELOAD
value. If the full path points to a nonexistent or unreadable file, mysqld_safe aborts with an error.For cases where mysqld_safe adds a path name to
LD_PRELOAD
, it adds the path to the beginning of any existing value the variable already has.
Linux users can use the
libtcmalloc_minimal.so
included in binary packages by adding these lines to themy.cnf
file:[mysqld_safe] malloc-lib=tcmalloc
Those lines also suffice for users on any platform who have installed a
tcmalloc
package in/usr/lib
. To use a specifictcmalloc
library, specify its full path name. Пример:[mysqld_safe] malloc-lib=/opt/lib/libtcmalloc_minimal.so
The name of the server program (in the
ledir
directory) that you want to start. This option is needed if you use the MySQL binary distribution but have the data directory outside of the binary distribution. If mysqld_safe cannot find the server, use the--ledir
option to indicate the path name to the directory where the server is located.This option is similar to the
--mysqld
option, but you specify only the suffix for the server program name. The basename is assumed to be mysqld. For example, if you use--mysqld-version=debug
, mysqld_safe starts the mysqld-debug program in theledir
directory. If the argument to--mysqld-version
is empty, mysqld_safe uses mysqld in theledir
directory.Use the
nice
program to set the server's scheduling priority to the given value.Do not read any option files. This must be the first option on the command line if it is used.
The number of files that mysqld should be able to open. The option value is passed to ulimit -n. Note that you need to start mysqld_safe as
root
for this to work properly!The path name of the process ID file.
The port number that the server should use when listening for TCP/IP connections. The port number must be 1024 or higher unless the server is started by the
root
system user.Do not try to kill stray mysqld processes at startup. This option works only on Linux.
The Unix socket file that the server should use when listening for local connections.
--syslog
causes error messages to be sent tosyslog
on systems that support the logger program.--skip-syslog
suppresses the use ofsyslog
; messages are written to an error log file.For logging to
syslog
, messages from mysqld_safe and mysqld are written with a tag ofmysqld_safe
andmysqld
, respectively. To specify a suffix for the tag, use--syslog-tag=
, which modifies the tags to betag
mysqld_safe-
andtag
mysqld-
.tag
Set the
TZ
time zone environment variable to the given option value. Consult your operating system documentation for legal time zone specification formats.Run the mysqld server as the user having the name
user_name
or the numeric user IDuser_id
. (“User” in this context refers to a system login account, not a MySQL user listed in the grant tables.)
If you execute mysqld_safe with the
--defaults-file
or
--defaults-extra-file
option
to name an option file, the option must be the first one given
on the command line or the option file will not be used. For
example, this command will not use the named option file:
mysql> mysqld_safe --port=port_num
--defaults-file=file_name
Instead, use the following command:
mysql> mysqld_safe --defaults-file=file_name
--port=port_num
The mysqld_safe script is written so that it normally can start a server that was installed from either a source or a binary distribution of MySQL, even though these types of distributions typically install the server in slightly different locations. (See Section 2.1.5, “Installation Layouts”.) mysqld_safe expects one of the following conditions to be true:
The server and databases can be found relative to the working directory (the directory from which mysqld_safe is invoked). For binary distributions, mysqld_safe looks under its working directory for
bin
anddata
directories. For source distributions, it looks forlibexec
andvar
directories. This condition should be met if you execute mysqld_safe from your MySQL installation directory (for example,/usr/local/mysql
for a binary distribution).If the server and databases cannot be found relative to the working directory, mysqld_safe attempts to locate them by absolute path names. Typical locations are
/usr/local/libexec
and/usr/local/var
. The actual locations are determined from the values configured into the distribution at the time it was built. They should be correct if MySQL is installed in the location specified at configuration time.
Because mysqld_safe tries to find the server and databases relative to its own working directory, you can install a binary distribution of MySQL anywhere, as long as you run mysqld_safe from the MySQL installation directory:
shell>cd
shell>mysql_installation_directory
bin/mysqld_safe &
If mysqld_safe fails, even when invoked from
the MySQL installation directory, you can specify the
--ledir
and
--datadir
options to
indicate the directories in which the server and databases are
located on your system.
Beginning with MySQL 5.5.21, mysqld_safe tries to use the sleep and date system utilities to determine how many times it has attempted to start this second, and—if these are present and this is greater than 5 times—is forced to wait 1 full second before starting again. This is intended to prevent excessive CPU usage in the event of repeated failures. (Bug #11761530, Bug #54035)
When you use mysqld_safe to start mysqld, mysqld_safe arranges for error (and notice) messages from itself and from mysqld to go to the same destination.
There are several mysqld_safe options for controlling the destination of these messages:
--syslog
: Write error messages tosyslog
on systems that support the logger program.--skip-syslog
: Do not write error messages tosyslog
. Messages are written to the default error log file (
in the data directory), or to a named file if thehost_name
.err--log-error
option is given.--log-error=
: Write error messages to the named error file.file_name
If none of these options is given, the default is
--skip-syslog
.
If --syslog
and
--log-error
are both given,
a warning is issued and
--log-error
takes
precedence.
When mysqld_safe writes a message, notices go
to the logging destination (syslog
or the
error log file) and stdout
. Ошибки go to the
logging destination and stderr
.
Normally, you should not edit the mysqld_safe
script. Instead, configure mysqld_safe by
using command-line options or options in the
[mysqld_safe]
section of a
my.cnf
option file. In rare cases, it might
be necessary to edit mysqld_safe to get it to
start the server properly. However, if you do this, your
modified version of mysqld_safe might be
overwritten if you upgrade MySQL in the future, so you should
make a copy of your edited version that you can reinstall.
MySQL distributions on Unix include a script named mysql.server. It can be used on systems such as Linux and Solaris that use System V-style run directories to start and stop system services. It is also used by the Mac OS X Startup Item for MySQL.
mysql.server can be found in the
support-files
directory under your MySQL
installation directory or in a MySQL source distribution.
If you use the Linux server RPM package
(MySQL-server-
),
the mysql.server script will be installed in
the VERSION
.rpm/etc/init.d
directory with the name
mysql
. You need not install it manually.
See Section 2.5.1, “Installing MySQL from RPM Packages on Linux”, for more
information on the Linux RPM packages.
Some vendors provide RPM packages that install a startup script under a different name such as mysqld.
If you install MySQL from a source distribution or using a binary distribution format that does not install mysql.server automatically, you can install it manually. Instructions are provided in Section 2.10.1.2, “Starting and Stopping MySQL Automatically”.
mysql.server reads options from the
[mysql.server]
and
[mysqld]
sections of option files. For
backward compatibility, it also reads
[mysql_server]
sections, although you should
rename such sections to [mysql.server]
when
using MySQL 5.5.
mysql.server supports the following options.
The path to the MySQL installation directory.
The path to the MySQL data directory.
The path name of the file in which the server should write its process ID.
--service-startup-timeout=
file_name
How long in seconds to wait for confirmation of server startup. If the server does not start within this time, mysql.server exits with an error. The default value is 900. A value of 0 means not to wait at all for startup. Negative values mean to wait forever (no timeout).
Use mysqld_safe to start the server. This is the default.
The login user name to use for running mysqld.
mysqld_multi is designed to manage several mysqld processes that listen for connections on different Unix socket files and TCP/IP ports. It can start or stop servers, or report their current status.
mysqld_multi searches for groups named
[mysqld
in
N
]my.cnf
(or in the file named by the
--config-file
option).
N
can be any positive integer. This
number is referred to in the following discussion as the option
group number, or GNR
. Group numbers
distinguish option groups from one another and are used as
arguments to mysqld_multi to specify which
servers you want to start, stop, or obtain a status report for.
Options listed in these groups are the same that you would use
in the [mysqld]
group used for starting
mysqld. (See, for example,
Section 2.10.1.2, “Starting and Stopping MySQL Automatically”.) However, when using multiple
servers, it is necessary that each one use its own value for
options such as the Unix socket file and TCP/IP port number. For
more information on which options must be unique per server in a
multiple-server environment, see
Section 5.6, “Running Multiple MySQL Instances on One Machine”.
To invoke mysqld_multi, use the following syntax:
shell> mysqld_multi [options
] {start|stop|report} [GNR
[,GNR
] ...]
start
, stop
, and
report
indicate which operation to perform.
You can perform the designated operation for a single server or
multiple servers, depending on the
GNR
list that follows the option
name. If there is no list, mysqld_multi
performs the operation for all servers in the option file.
Each GNR
value represents an option
group number or range of group numbers. The value should be the
number at the end of the group name in the option file. For
example, the GNR
for a group named
[mysqld17]
is 17
. To
specify a range of numbers, separate the first and last numbers
by a dash. The GNR
value
10-13
represents groups
[mysqld10]
through
[mysqld13]
. Multiple groups or group ranges
can be specified on the command line, separated by commas. There
must be no whitespace characters (spaces or tabs) in the
GNR
list; anything after a whitespace
character is ignored.
This command starts a single server using option group
[mysqld17]
:
shell> mysqld_multi start 17
This command stops several servers, using option groups
[mysqld8]
and [mysqld10]
through [mysqld13]
:
shell> mysqld_multi stop 8,10-13
For an example of how you might set up an option file, use this command:
shell> mysqld_multi --example
mysqld_multi searches for option files as follows:
With
--no-defaults
, no option files are read.With
--defaults-file=
, only the named file is read.file_name
Otherwise, option files in the standard list of locations are read, including any file named by the
--defaults-extra-file=
option, if one is given. (If the option is given multiple times, the last value is used.)file_name
Option files read are searched for
[mysqld_multi]
and
[mysqld
option
groups. The N
][mysqld_multi]
group can be used
for options to mysqld_multi itself.
[mysqld
groups
can be used for options passed to specific
mysqld instances.
N
]
The [mysqld]
or
[mysqld_safe]
groups can be used for common
options read by all instances of mysqld or
mysqld_safe. You can specify a
--defaults-file=
option to use a different configuration file for that instance,
in which case the file_name
[mysqld]
or
[mysqld_safe]
groups from that file will be
used for that instance.
mysqld_multi supports the following options.
Display a help message and exit.
This option is deprecated. If given, it is treated the same way as
--defaults-extra-file
, described earlier.--config-file
was removed in MySQL 5.5.3.Display a sample option file.
Specify the name of the log file. If the file exists, log output is appended to it.
The mysqladmin binary to be used to stop servers.
The mysqld binary to be used. Note that you can specify mysqld_safe as the value for this option also. If you use mysqld_safe to start the server, you can include the
mysqld
orledir
options in the corresponding[mysqld
option group. These options indicate the name of the server that mysqld_safe should start and the path name of the directory where the server is located. (See the descriptions for these options in Section 4.3.2, “mysqld_safe — MySQL Server Startup Script”.) Пример:N
][mysqld38] mysqld = mysqld-debug ledir = /opt/local/mysql/libexec
Print log information to
stdout
rather than to the log file. By default, output goes to the log file.The password of the MySQL account to use when invoking mysqladmin. Note that the password value is not optional for this option, unlike for other MySQL programs.
Silent mode; disable warnings.
Connect to each MySQL server through the TCP/IP port instead of the Unix socket file. (If a socket file is missing, the server might still be running, but accessible only through the TCP/IP port.) By default, connections are made using the Unix socket file. This option affects
stop
andreport
operations.The user name of the MySQL account to use when invoking mysqladmin.
Be more verbose.
Display version information and exit.
Some notes about mysqld_multi:
Most important: Before using mysqld_multi be sure that you understand the meanings of the options that are passed to the mysqld servers and why you would want to have separate mysqld processes. Beware of the dangers of using multiple mysqld servers with the same data directory. Use separate data directories, unless you know what you are doing. Starting multiple servers with the same data directory does not give you extra performance in a threaded system. See Section 5.6, “Running Multiple MySQL Instances on One Machine”.
- Important
Make sure that the data directory for each server is fully accessible to the Unix account that the specific mysqld process is started as. Do not use the Unix
root
account for this, unless you know what you are doing. See Section 5.3.6, “How to Run MySQL as a Normal User”. Make sure that the MySQL account used for stopping the mysqld servers (with the mysqladmin program) has the same user name and password for each server. Also, make sure that the account has the
SHUTDOWN
privilege. If the servers that you want to manage have different user names or passwords for the administrative accounts, you might want to create an account on each server that has the same user name and password. For example, you might set up a commonmulti_admin
account by executing the following commands for each server:shell>
mysql -u root -S /tmp/mysql.sock -p
Enter password: mysql>GRANT SHUTDOWN ON *.*
->TO 'multi_admin'@'localhost' IDENTIFIED BY 'multipass';
See Section 5.4, “The MySQL Access Privilege System”. You have to do this for each mysqld server. Change the connection parameters appropriately when connecting to each one. Note that the host name part of the account name must permit you to connect as
multi_admin
from the host where you want to run mysqld_multi.The Unix socket file and the TCP/IP port number must be different for every mysqld. (Alternatively, if the host has multiple network addresses, you can use
--bind-address
to cause different servers to listen to different interfaces.)The
--pid-file
option is very important if you are using mysqld_safe to start mysqld (for example,--mysqld=mysqld_safe
) Every mysqld should have its own process ID file. The advantage of using mysqld_safe instead of mysqld is that mysqld_safe monitors its mysqld process and restarts it if the process terminates due to a signal sent usingkill -9
or for other reasons, such as a segmentation fault. Please note that the mysqld_safe script might require that you start it from a certain place. This means that you might have to change location to a certain directory before running mysqld_multi. If you have problems starting, please see the mysqld_safe script. Check especially the lines:---------------------------------------------------------------- MY_PWD=`pwd` # Check if we are starting this relative (for the binary release) if test -d $MY_PWD/data/mysql -a \ -f ./share/mysql/english/errmsg.sys -a \ -x ./bin/mysqld ----------------------------------------------------------------
The test performed by these lines should be successful, or you might encounter problems. See Section 4.3.2, “mysqld_safe — MySQL Server Startup Script”.
You might want to use the
--user
option for mysqld, but to do this you need to run the mysqld_multi script as the Unix superuser (root
). Having the option in the option file doesn't matter; you just get a warning if you are not the superuser and the mysqld processes are started under your own Unix account.
The following example shows how you might set up an option file
for use with mysqld_multi. The order in which
the mysqld programs are started or stopped
depends on the order in which they appear in the option file.
Group numbers need not form an unbroken sequence. The first and
fifth [mysqld
groups were intentionally omitted from the example to illustrate
that you can have “gaps” in the option file. This
gives you more flexibility.
N
]
# This file should probably be in your home dir (~/.my.cnf) # or /etc/my.cnf # Version 2.1 by Jani Tolonen [mysqld_multi] mysqld = /usr/local/bin/mysqld_safe mysqladmin = /usr/local/bin/mysqladmin user = multi_admin password = multipass [mysqld2] socket = /tmp/mysql.sock2 port = 3307 pid-file = /usr/local/mysql/var2/hostname.pid2 datadir = /usr/local/mysql/var2 language = /usr/local/share/mysql/english user = john [mysqld3] socket = /tmp/mysql.sock3 port = 3308 pid-file = /usr/local/mysql/var3/hostname.pid3 datadir = /usr/local/mysql/var3 language = /usr/local/share/mysql/swedish user = monty [mysqld4] socket = /tmp/mysql.sock4 port = 3309 pid-file = /usr/local/mysql/var4/hostname.pid4 datadir = /usr/local/mysql/var4 language = /usr/local/share/mysql/estonia user = tonu [mysqld6] socket = /tmp/mysql.sock6 port = 3311 pid-file = /usr/local/mysql/var6/hostname.pid6 datadir = /usr/local/mysql/var6 language = /usr/local/share/mysql/japanese user = jani
- 4.4.1. comp_err — Compile MySQL Error Message File
- 4.4.2. mysqlbug — Generate Bug Report
- 4.4.3. mysql_install_db — Initialize MySQL Data Directory
- 4.4.4. mysql_plugin — Configure MySQL Server Plugins
- 4.4.5. mysql_secure_installation — Improve MySQL Installation Security
- 4.4.6. mysql_tzinfo_to_sql — Load the Time Zone Tables
- 4.4.7. mysql_upgrade — Check Tables for MySQL Upgrade
The programs in this section are used when installing or upgrading MySQL.
comp_err creates the
errmsg.sys
file that is used by
mysqld to determine the error messages to
display for different error codes. comp_err
normally is run automatically when MySQL is built. It compiles
the errmsg.sys
file from the plaintext file
located at sql/share/errmsg.txt
in MySQL
source distributions.
comp_err also generates
mysqld_error.h
,
mysqld_ername.h
, and
sql_state.h
header files.
For more information about how error messages are defined, see the MySQL Internals Manual, available at http://forge.mysql.com/wiki/MySQL_Internals.
Invoke comp_err like this:
shell> comp_err [options
]
comp_err supports the following options.
--help
,-?
Display a help message and exit.
--charset=
,path
-C
path
The character set directory. The default is
../sql/share/charsets
.--debug=
,debug_options
-#
debug_options
Write a debugging log. A typical
debug_options
string is'd:t:O,
. The default isfile_name
''d:t:O,/tmp/comp_err.trace'
.--debug-info
,-T
Print some debugging information when the program exits.
--header_file=
,file_name
-H
file_name
The name of the error header file. The default is
mysqld_error.h
.--in_file=
,file_name
-F
file_name
The name of the input file. The default is
../sql/share/errmsg.txt
.--name_file=
,file_name
-N
file_name
The name of the error name file. The default is
mysqld_ername.h
.--out_dir=
,path
-D
path
The name of the output base directory. The default is
../sql/share/
.--out_file=
,file_name
-O
file_name
The name of the output file. The default is
errmsg.sys
.--statefile=
,file_name
-S
file_name
The name for the SQLSTATE header file. The default is
sql_state.h
.--version
,-V
Display version information and exit.
This program is obsolete.
The normal way to report bugs is to visit http://bugs.mysql.com/, which is the address for our bugs database. This database is public and can be browsed and searched by anyone. If you log in to the system, you can enter new reports.
mysql_install_db initializes the MySQL data directory and creates the system tables that it contains, if they do not exist.
To invoke mysql_install_db, use the following syntax:
shell> mysql_install_db [options
]
Because the MySQL server, mysqld, needs to
access the data directory when it runs later, you should either
run mysql_install_db from the same account
that will be used for running mysqld or run
it as root
and use the
--user
option to
indicate the user name that mysqld will run
as. It might be necessary to specify other options such as
--basedir
or
--datadir
if
mysql_install_db does not use the correct
locations for the installation directory or data directory. For
example:
shell>scripts/mysql_install_db --user=mysql \
--basedir=/opt/mysql/mysql \
--datadir=/opt/mysql/mysql/data
mysql_install_db needs to invoke
mysqld with the
--bootstrap
and
--skip-grant-tables
options. If
MySQL was configured with the
DISABLE_GRANT_OPTIONS
compiler
flag, --bootstrap
and
--skip-grant-tables
will be
disabled (see Section 2.9.4, “MySQL Source-Configuration Options”).
To handle this, set the MYSQLD_BOOTSTRAP
environment variable to the full path name of a server that has
all options enabled. mysql_install_db will
use that server.
If you have set a custom TMPDIR
variable
when performing the installation, and the specified directory
is not accessible, the execution of
mysql_install_db may fail. You should unset
TMPDIR
, or set TMPDIR
to
point to the system temporary directory (usually
/tmp
).
mysql_install_db supports the following
options, which can be specified on the command line or in the
[mysql_install_db]
and (if they are common to
mysqld) [mysqld]
groups of
an option file. Other options are passed to
mysqld. For information about option files,
see Section 4.2.3.3, “Using Option Files”.
mysql_install_db also supports the options
for processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
The path to the MySQL installation directory.
Cause mysql_install_db to run even if DNS does not work. In that case, grant table entries that normally use host names will use IP addresses.
The path to the MySQL data directory.
For internal use. This option is used by RPM files during the MySQL installation process.
Use IP addresses rather than host names when creating grant table entries. This option can be useful if your DNS does not work.
For internal use. The directory under which mysql_install_db looks for support files such as the error message file and the file for populating the help tables.
The login user name to use for running mysqld. Files and directories created by mysqld will be owned by this user. You must be
root
to use this option. By default, mysqld runs using your current login name and files and directories that it creates will be owned by you.Verbose mode. Print more information about what the program does.
For internal use. This option is used for creating Windows distributions.
The mysql_plugin utility enables MySQL
administrators to manage which plugins a MySQL server loads. It
provides an alternative to manually specifying the
--plugin-load
option at server
startup or using the INSTALL
PLUGIN
and UNINSTALL
PLUGIN
statements at runtime.
mysql_plugin is available as of MySQL 5.5.16.
Depending on whether mysql_plugin is invoked
to enable or disable plugins, it inserts or deletes rows in the
mysql.plugin
table that serves as a plugin
registry. (To perform this operation,
mysql_plugin invokes the MySQL server in
bootstrap mode. This means that the server must not already be
running.) For normal server startups, the server loads and
enables plugins listed in mysql.plugin
automatically. For additional control over plugin activation,
use --
options named for specific plugins, as described in
Section 5.1.7.1, “Installing and Uninstalling Plugins”.
plugin_name
Each invocation of mysql_plugin reads a configuration file to determine how to configure the plugins contained in a single plugin library object file. To invoke mysql_plugin, use this syntax:
mysql_plugin [options
]plugin
{ENABLE|DISABLE}
plugin
is the name of the plugin to
configure. ENABLE
or
DISABLE
(not case sensitive) specify whether
to enable or disable components of the plugin library named in
the configuration file. The order of the
plugin
and ENABLE
or DISABLE
arguments does not matter.
For example, to configure components of a plugin library file
named myplugins.so
on Linux or
myplugins.dll
on Windows, specify a
plugin
value of
myplugins
. Suppose that this plugin library
contains three plugins, plugin1
,
plugin2
, and plugin3
, all
of which should be configured under
mysql_plugin control. By convention,
configuration files have a suffix of .ini
and the same basename as the plugin library, so the default
configuration file name for this plugin library is
myplugins.ini
. The configuration file
contents look like this:
myplugins plugin1 plugin2 plugin3
The first line in the myplugins.ini
file is
the name of the library object file, without any extension such
as .so
or .dll
. The
remaining lines are the names of the components to be enabled or
disabled. Each value in the file should be on a separate line.
Lines on which the first character is '#'
are
taken as comments and ignored.
To enable the plugins listed in the configuration file, invoke mysql_plugin this way:
shell> mysql_plugin myplugins ENABLE
To disable the plugins, use DISABLE
rather
than ENABLE
.
An error occurs if mysql_plugin cannot find the configuration file or plugin library file, or if mysql_plugin cannot start the MySQL server.
mysql_plugin supports the following options,
which can be specified on the command line or in the
[mysqld]
group of any option file. For
options specified in a [mysqld]
group,
mysql_plugin recognizes the
--basedir
,
--datadir
, and
--plugin-dir
options and
ignores others. For information about option files, see
Section 4.2.3.3, “Using Option Files”.
mysql_plugin
Options
--help
,-?
Display a help message and exit.
--basedir=
,path
-b
path
The server base directory.
--datadir=
,path
-d
path
The server data directory.
--my-print-defaults=
,path
-b
path
The path to the my_print_defaults program.
--mysqld=
,path
-b
path
The path to the mysqld server.
--no-defaults
,-p
Do not read values from the configuration file. This option enables an administrator to skip reading defaults from the configuration file.
With mysql_plugin, this option need not be given first on the command line, unlike most other MySQL programs that support
--no-defaults
.--plugin-dir=
,path
-p
path
The server plugin directory.
--plugin-ini=
,file_name
-i
file_name
The mysql_plugin configuration file. Relative path names are interpreted relative to the current directory. If this option is not given, the default is
in the plugin directory, whereplugin
.iniplugin
is theplugin
argument on the command line.--print-defaults
,-P
Display the default values from the configuration file. This option causes mysql_plugin to print the defaults for
--basedir
,--datadir
, and--plugin-dir
if they are found in the configuration file. If no value for a variable is found, nothing is shown.With mysql_plugin, this option need not be given first on the command line, unlike most other MySQL programs that support
--print-defaults
.--verbose
,-v
Verbose mode. Print more information about what the program does. This option can be used multiple times to increase the amount of information.
--version
,-V
Display version information and exit.
This program enables you to improve the security of your MySQL installation in the following ways:
You can set a password for
root
accounts.You can remove
root
accounts that are accessible from outside the local host.You can remove anonymous-user accounts.
You can remove the
test
database (which by default can be accessed by all users, even anonymous users), and privileges that permit anyone to access databases with names that start withtest_
.
mysql_secure_installation helps you implement security recommendations similar to those described at Section 2.10.2, “Securing the Initial MySQL Accounts”.
Invoke mysql_secure_installation without arguments:
shell> mysql_secure_installation
The script will prompt you to determine which actions to perform.
mysql_secure_installation is not available on Windows.
The mysql_tzinfo_to_sql program loads the
time zone tables in the mysql
database. It is
used on systems that have a zoneinfo
database (the set of files describing time zones). Examples of
such systems are Linux, FreeBSD, Solaris, and Mac OS X. One
likely location for these files is the
/usr/share/zoneinfo
directory
(/usr/share/lib/zoneinfo
on Solaris). If
your system does not have a zoneinfo database, you can use the
downloadable package described in
Section 9.6, “MySQL Server Time Zone Support”.
mysql_tzinfo_to_sql can be invoked several ways:
shell>mysql_tzinfo_to_sql
shell>tz_dir
mysql_tzinfo_to_sql
shell>tz_file tz_name
mysql_tzinfo_to_sql --leap
tz_file
For the first invocation syntax, pass the zoneinfo directory path name to mysql_tzinfo_to_sql and send the output into the mysql program. For example:
shell> mysql_tzinfo_to_sql /usr/share/zoneinfo | mysql -u root mysql
mysql_tzinfo_to_sql reads your system's time zone files and generates SQL statements from them. mysql processes those statements to load the time zone tables.
The second syntax causes mysql_tzinfo_to_sql
to load a single time zone file
tz_file
that corresponds to a time
zone name tz_name
:
shell> mysql_tzinfo_to_sql tz_file
tz_name
| mysql -u root mysql
If your time zone needs to account for leap seconds, invoke
mysql_tzinfo_to_sql using the third syntax,
which initializes the leap second information.
tz_file
is the name of your time zone
file:
shell> mysql_tzinfo_to_sql --leap tz_file
| mysql -u root mysql
After running mysql_tzinfo_to_sql, it is best to restart the server so that it does not continue to use any previously cached time zone data.
mysql_upgrade examines all tables in all databases for incompatibilities with the current version of MySQL Server. mysql_upgrade also upgrades the system tables so that you can take advantage of new privileges or capabilities that might have been added.
mysql_upgrade should be executed each time you upgrade MySQL. It supersedes the older mysql_fix_privilege_tables script, which has been removed in MySQL 5.5.
If mysql_upgrade finds that a table has a possible incompatibility, it performs a table check and, if problems are found, attempts a table repair. If the table cannot be repaired, see Section 2.11.4, “Rebuilding or Repairing Tables or Indexes” for manual table repair strategies.
On Windows Server 2008, Vista, and newer, you must run mysql_upgrade with administrator privileges. You can do this by running a Command Prompt as Administrator and running the command. Failure to do so may result in the upgrade failing to execute correctly.
You should always back up your current MySQL installation before performing an upgrade. See Section 6.2, “Database Backup Methods”.
Some upgrade incompatibilities may require special handling before you upgrade your MySQL installation and run mysql_upgrade. See Section 2.11.1, “Upgrading MySQL”, for instructions on determining whether any such incompatibilities apply to your installation and how to handle them.
To use mysql_upgrade, make sure that the server is running, and then invoke it like this:
shell> mysql_upgrade [options
]
After running mysql_upgrade, stop the server and restart it so that any changes made to the system tables take effect.
mysql_upgrade executes the following commands to check and repair tables and to upgrade the system tables:
mysqlcheck --all-databases --check-upgrade --auto-repair
mysql < fix_priv_tables
mysqlcheck --all-databases --check-upgrade --fix-db-names --fix-table-names
Notes about the preceding commands:
Because mysql_upgrade invokes mysqlcheck with the
--all-databases
option, it processes all tables in all databases, which might take a long time to complete. Each table is locked and therefore unavailable to other sessions while it is being processed. Check and repair operations can be time-consuming, particularly for large tables.For details about what checks the
--check-upgrade
option entails, see the description of theFOR UPGRADE
option of theCHECK TABLE
statement (see Section 12.7.2.2, “CHECK TABLE
Синтаксис”).fix_priv_tables
represents a script generated internally by mysql_upgrade that contains SQL statements to upgrade the tables in themysql
database.
All checked and repaired tables are marked with the current MySQL version number. This ensures that next time you run mysql_upgrade with the same version of the server, it can tell whether there is any need to check or repair the table again.
mysql_upgrade also saves the MySQL version
number in a file named mysql_upgrade_info
in the data directory. This is used to quickly check whether all
tables have been checked for this release so that table-checking
can be skipped. To ignore this file and perform the check
regardless, use the
--force
option.
If you install MySQL from RPM packages on Linux, you must install the server and client RPMs. mysql_upgrade is included in the server RPM but requires the client RPM because the latter includes mysqlcheck. (See Section 2.5.1, “Installing MySQL from RPM Packages on Linux”.)
mysql_upgrade does not upgrade the contents of the help tables. For upgrade instructions, see Section 5.1.8, “Server-Side Help”.
mysql_upgrade supports the following options,
which can be specified on the command line or in the
[mysql_upgrade]
and
[client]
groups of an option file. Other
options are passed to mysqlcheck. For
example, it might be necessary to specify the
--password[=
option. mysql_upgrade also supports the
options for processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
password
]
Display a short help message and exit.
The path to the MySQL installation directory. This option is accepted for backward compatibility but ignored.
The path to the data directory. This option is accepted for backward compatibility but ignored.
Print some debugging information when the program exits.
--debug-info
,-T
Print debugging information and memory and CPU usage statistics when the program exits.
The client-side authentication plugin to use. See Section 5.5.6, “Pluggable Authentication”.
This option was added in MySQL 5.5.10.
Ignore the
mysql_upgrade_info
file and force execution of mysqlcheck even if mysql_upgrade has already been executed for the current version of MySQL.The directory in which to look for plugins. It may be necessary to specify this option if the
--default-auth
option is used to specify an authentication plugin but mysql_upgrade does not find it. See Section 5.5.6, “Pluggable Authentication”.This option was added in MySQL 5.5.10.
--tmpdir=
,path
-t
path
The path name of the directory to use for creating temporary files.
Upgrade only the system tables, do not upgrade data.
--user=
,user_name
-u
user_name
The MySQL user name to use when connecting to the server. The default user name is
root
.Verbose mode. Print more information about what the program does.
Cause binary logging to be enabled while mysql_upgrade runs. This is the default behavior; to disable binary logging during the upgrade, use the inverse of this option (that is, start the program with
--skip-write-binlog
).
- 4.5.1. mysql — The MySQL Command-Line Tool
- 4.5.2. mysqladmin — Client for Administering a MySQL Server
- 4.5.3. mysqlcheck — A Table Maintenance Program
- 4.5.4. mysqldump — A Database Backup Program
- 4.5.5. mysqlimport — A Data Import Program
- 4.5.6. mysqlshow — Display Database, Table, and Column Information
- 4.5.7. mysqlslap — Load Emulation Client
This section describes client programs that connect to the MySQL server.
mysql is a simple SQL shell (with GNU
readline
capabilities). It supports
interactive and noninteractive use. When used interactively,
query results are presented in an ASCII-table format. When used
noninteractively (for example, as a filter), the result is
presented in tab-separated format. The output format can be
changed using command options.
If you have problems due to insufficient memory for large result
sets, use the --quick
option. This
forces mysql to retrieve results from the
server a row at a time rather than retrieving the entire result
set and buffering it in memory before displaying it. This is
done by returning the result set using the
mysql_use_result()
C API
function in the client/server library rather than
mysql_store_result()
.
Using mysql is very easy. Invoke it from the prompt of your command interpreter as follows:
shell> mysql db_name
Or:
shell> mysql --user=user_name
--password=your_password
db_name
Then type an SQL statement, end it with
“;
”, \g
, or
\G
and press Enter.
Typing Control+C causes mysql to attempt to kill the current statement. If this cannot be done, or Control+C is typed again before the statement is killed, mysql exits. Previously, Control+C caused mysql to exit in all cases.
You can execute SQL statements in a script file (batch file) like this:
shell> mysql db_name
< script.sql
> output.tab
On Unix, the mysql client writes a record of executed statements to a history file. See Section 4.5.1.3, “mysql History File”.
mysql supports the following options, which
can be specified on the command line or in the
[mysql]
and [client]
groups of an option file. mysql also supports
the options for processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
Table 4.2. mysql
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--auto-rehash | auto-rehash | Enable automatic rehashing | |||
--auto-vertical-output | auto-vertical-output | Enable automatic vertical result set display | 5.5.3 | ||
--batch | batch | Don't use history file | |||
--character-sets-dir=path | character-sets-dir | Set the default character set | |||
--column-names | column-names | Write column names in results | |||
--column-type-info | column-type-info | Display result set metadata | |||
--comments | comments | Whether to retain or strip comments in statements sent to the server | |||
--compress | compress | Compress all information sent between the client and the server | |||
--connect_timeout=value | connect_timeout | The number of seconds before connection timeout | |||
--database=dbname | database | The database to use | |||
--debug[=debug_options] | debug | Write a debugging log | |||
--debug-check | debug-check | Print debugging information when the program exits | |||
--debug-info | debug-info | Print debugging information, memory and CPU statistics when the program exits | |||
--default-auth=plugin | default-auth=plugin | The authentication plugin to use | 5.5.7 | ||
--default-character-set=charset_name | default-character-set | Use charset_name as the default character set | |||
--delimiter=str | delimiter | Set the statement delimiter | |||
--execute=statement | execute | Execute the statement and quit | |||
--force | force | Continue even if an SQL error occurs | |||
--help | Display help message and exit | ||||
--host=host_name | host | Connect to the MySQL server on the given host | |||
--html | html | Produce HTML output | |||
--ignore-spaces | ignore-spaces | Ignore spaces after function names | |||
--line-numbers | line-numbers | Write line numbers for errors | |||
--local-infile[={0|1}] | local-infile | Enable or disable for LOCAL capability for LOAD DATA INFILE | |||
--max_allowed_packet=value | max_allowed_packet | The maximum packet length to send to or receive from the server | |||
--max_join_size=value | max_join_size | The automatic limit for rows in a join when using --safe-updates | |||
--named-commands | named-commands | Enable named mysql commands | |||
--net_buffer_length=value | net_buffer_length | The buffer size for TCP/IP and socket communication | |||
--no-auto-rehash | Disable automatic rehashing | ||||
--no-beep | no-beep | Do not beep when errors occur | |||
--no-named-commands | no-named-commands | Disable named mysql commands | 5.5.3 | ||
--no-pager | no-pager | Deprecated form of --skip-pager | 5.5.3 | ||
--no-tee | no-tee | Do not copy output to a file | 5.5.3 | ||
--one-database | one-database | Ignore statements except those for the default database named on the command line | |||
--pager[=command] | pager | Use the given command for paging query output | |||
--password[=password] | password | The password to use when connecting to the server | |||
--plugin-dir=path | plugin-dir=path | The directory where plugins are located | 5.5.7 | ||
--port=port_num | port | The TCP/IP port number to use for the connection | |||
--prompt=format_str | prompt | Set the prompt to the specified format | |||
--protocol=type | protocol | The connection protocol to use | |||
--quick | quick | Do not cache each query result | |||
--raw | raw | Write column values without escape conversion | |||
--reconnect | reconnect | If the connection to the server is lost, automatically try to reconnect | |||
--safe-updates | safe-updates | Allow only UPDATE and DELETE statements that specify key values | |||
--secure-auth | secure-auth | Do not send passwords to the server in old (pre-4.1.1) format | |||
--select_limit=value | select_limit | The automatic limit for SELECT statements when using --safe-updates | |||
--show-warnings | show-warnings | Show warnings after each statement if there are any | |||
--sigint-ignore | sigint-ignore | Ignore SIGINT signals (typically the result of typing Control+C) | |||
--silent | silent | Silent mode | |||
--skip-auto-rehash | skip-auto-rehash | Disable automatic rehashing | |||
--skip-column-names | skip-column-names | Do not write column names in results | |||
--skip-line-numbers | skip-line-numbers | Skip line numbers for errors | |||
--skip-named-commands | skip-named-commands | Disable named mysql commands | |||
--skip-pager | skip-pager | Disable paging | |||
--skip-reconnect | skip-reconnect | Disable reconnecting | |||
--socket=path | socket | For connections to localhost | |||
--ssl-ca=file_name | ssl-ca | The path to a file that contains a list of trusted SSL CAs | |||
--ssl-capath=dir_name | ssl-capath | The path to a directory that contains trusted SSL CA certificates in PEM format | |||
--ssl-cert=file_name | ssl-cert | The name of the SSL certificate file to use for establishing a secure connection | |||
--ssl-cipher=cipher_list | ssl-cipher | A list of allowable ciphers to use for SSL encryption | |||
--ssl-key=file_name | ssl-key | The name of the SSL key file to use for establishing a secure connection | |||
--ssl-verify-server-cert | ssl-verify-server-cert | The server's Common Name value in its certificate is verified against the host name used when connecting to the server | |||
--table | table | Display output in tabular format | |||
--tee=file_name | tee | Append a copy of output to the given file | |||
--unbuffered | unbuffered | Flush the buffer after each query | |||
--user=user_name | user | The MySQL user name to use when connecting to the server | |||
--verbose | Verbose mode | ||||
--version | Display version information and exit | ||||
--vertical | vertical | Print query output rows vertically (one line per column value) | |||
--wait | wait | If the connection cannot be established, wait and retry instead of aborting | |||
--xml | xml | Produce XML output |
--help
,-?
Display a help message and exit.
Enable automatic rehashing. This option is on by default, which enables database, table, and column name completion. Use
--disable-auto-rehash
to disable rehashing. That causes mysql to start faster, but you must issue therehash
command if you want to use name completion.To complete a name, enter the first part and press Tab. If the name is unambiguous, mysql completes it. Otherwise, you can press Tab again to see the possible names that begin with what you have typed so far. Completion does not occur if there is no default database.
Cause result sets to be displayed vertically if they are too wide for the current window, and using normal tabular format otherwise. (This applies to statements terminated by
;
or\G
.) This option was added in MySQL 5.5.3.--batch
,-B
Print results using tab as the column separator, with each row on a new line. With this option, mysql does not use the history file.
Batch mode results in nontabular output format and escaping of special characters. Escaping may be disabled by using raw mode; see the description for the
--raw
option.On a computer having multiple network interfaces, this option can be used to select which interface is employed when connecting to the MySQL server.
This option is supported only in the version of the mysql client that is supplied with MySQL Cluster. It is not available in standard MySQL Server 5.5 releases.
The directory where character sets are installed. See Section 9.5, “Character Set Configuration”.
Write column names in results.
Display result set metadata.
--comments
,-c
Whether to preserve comments in statements sent to the server. The default is --skip-comments (discard comments), enable with --comments (preserve comments).
--compress
,-C
Compress all information sent between the client and the server if both support compression.
--database=
,db_name
-D
db_name
The database to use. This is useful primarily in an option file.
--debug[=
,debug_options
]-# [
debug_options
]Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default isfile_name
''d:t:o,/tmp/mysql.trace'
.Print some debugging information when the program exits.
--debug-info
,-T
Print debugging information and memory and CPU usage statistics when the program exits.
The client-side authentication plugin to use. See Section 5.5.6, “Pluggable Authentication”.
This option was added in MySQL 5.5.7.
--default-character-set=
charset_name
Use
charset_name
as the default character set for the client and connection.A common issue that can occur when the operating system uses
utf8
or another multi-byte character set is that output from the mysql client is formatted incorrectly, due to the fact that the MySQL client uses thelatin1
character set by default. You can usually fix such issues by using this option to force the client to use the system character set instead.See Section 9.5, “Character Set Configuration”, for more information.
Set the statement delimiter. The default is the semicolon character (“
;
”).Disable named commands. Use the
\*
form only, or use named commands only at the beginning of a line ending with a semicolon (“;
”). mysql starts with this option enabled by default. However, even with this option, long-format commands still work from the first line. See Section 4.5.1.2, “mysql Commands”.--execute=
,statement
-e
statement
Execute the statement and quit. The default output format is like that produced with
--batch
. See Section 4.2.3.1, “Using Options on the Command Line”, for some examples. With this option, mysql does not use the history file.--force
,-f
Continue even if an SQL error occurs.
--host=
,host_name
-h
host_name
Connect to the MySQL server on the given host.
--html
,-H
Produce HTML output.
--ignore-spaces
,-i
Ignore spaces after function names. The effect of this is described in the discussion for the
IGNORE_SPACE
SQL mode (see Section 5.1.6, “Server SQL Modes”).Write line numbers for errors. Disable this with
--skip-line-numbers
.Enable or disable
LOCAL
capability forLOAD DATA INFILE
. With no value, the option enablesLOCAL
. The option may be given as--local-infile=0
or--local-infile=1
to explicitly disable or enableLOCAL
. EnablingLOCAL
has no effect if the server does not also support it.--named-commands
,-G
Enable named mysql commands. Long-format commands are permitted, not just short-format commands. For example,
quit
and\q
both are recognized. Use--skip-named-commands
to disable named commands. See Section 4.5.1.2, “mysql Commands”.--no-auto-rehash
,-A
This has the same effect as
-skip-auto-rehash
. See the description for--auto-rehash
.--no-beep
,-b
Do not beep when errors occur.
Deprecated, use
--disable-named-commands
instead.--no-named-commands
was removed in MySQL 5.5.3.Deprecated form of
--skip-pager
. See the--pager
option.--no-pager
was removed in MySQL 5.5.3.Deprecated form of
--skip-tee
. See the--tee
option.--no-tee
is removed in MySQL 5.5.3.--one-database
,-o
Ignore statements except those that occur while the default database is the one named on the command line. This option is rudimentary and should be used with care. Statement filtering is based only on
USE
statements.Initially, mysql executes statements in the input because specifying a database
db_name
on the command line is equivalent to insertingUSE
at the beginning of the input. Then, for eachdb_name
USE
statement encountered, mysql accepts or rejects following statements depending on whether the database named is the one on the command line. The content of the statements is immaterial.Suppose that mysql is invoked to process this set of statements:
DELETE FROM db2.t2; USE db2; DROP TABLE db1.t1; CREATE TABLE db1.t1 (i INT); USE db1; INSERT INTO t1 (i) VALUES(1); CREATE TABLE db2.t1 (j INT);
If the command line is mysql --force --one-database db1, mysql handles the input as follows:
The
DELETE
statement is executed because the default database isdb1
, even though the statement names a table in a different database.The
DROP TABLE
andCREATE TABLE
statements are not executed because the default database is notdb1
, even though the statements name a table indb1
.The
INSERT
andCREATE TABLE
statements are executed because the default database isdb1
, even though theCREATE TABLE
statement names a table in a different database.
Use the given command for paging query output. If the command is omitted, the default pager is the value of your
PAGER
environment variable. Valid pagers are less, more, cat [> filename], and so forth. This option works only on Unix and only in interactive mode. To disable paging, use--skip-pager
. Section 4.5.1.2, “mysql Commands”, discusses output paging further.--password[=
,password
]-p[
password
]The password to use when connecting to the server. If you use the short option form (
-p
), you cannot have a space between the option and the password. If you omit thepassword
value following the--password
or-p
option on the command line, mysql prompts for one.Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
--pipe
,-W
On Windows, connect to the server using a named pipe. This option applies only if the server supports named-pipe connections.
The directory in which to look for plugins. It may be necessary to specify this option if the
--default-auth
option is used to specify an authentication plugin but mysql does not find it. See Section 5.5.6, “Pluggable Authentication”.This option was added in MySQL 5.5.7.
--port=
,port_num
-P
port_num
The TCP/IP port number to use for the connection.
Set the prompt to the specified format. The default is
mysql>
. The special sequences that the prompt can contain are described in Section 4.5.1.2, “mysql Commands”.--protocol={TCP|SOCKET|PIPE|MEMORY}
The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the permissible values, see Section 4.2.2, “Connecting to the MySQL Server”.
--quick
,-q
Do not cache each query result, print each row as it is received. This may slow down the server if the output is suspended. With this option, mysql does not use the history file.
--raw
,-r
For tabular output, the “boxing” around columns enables one column value to be distinguished from another. For nontabular output (such as is produced in batch mode or when the
--batch
or--silent
option is given), special characters are escaped in the output so they can be identified easily. Newline, tab,NUL
, and backslash are written as\n
,\t
,\0
, and\\
. The--raw
option disables this character escaping.The following example demonstrates tabular versus nontabular output and the use of raw mode to disable escaping:
%
mysql
mysql> SELECT CHAR(92); +----------+ | CHAR(92) | +----------+ | \ | +----------+ %mysql -s
mysql> SELECT CHAR(92); CHAR(92) \\ %mysql -s -r
mysql> SELECT CHAR(92); CHAR(92) \If the connection to the server is lost, automatically try to reconnect. A single reconnect attempt is made each time the connection is lost. To suppress reconnection behavior, use
--skip-reconnect
.--safe-updates
,--i-am-a-dummy
,-U
Permit only those
UPDATE
andDELETE
statements that specify which rows to modify by using key values. If you have set this option in an option file, you can override it by using--safe-updates
on the command line. See Section 4.5.1.6, “mysql Tips”, for more information about this option.Do not send passwords to the server in old (pre-4.1.1) format. This prevents connections except for servers that use the newer password format.
Cause warnings to be shown after each statement if there are any. This option applies to interactive and batch mode.
Ignore
SIGINT
signals (typically the result of typing Control+C).--silent
,-s
Silent mode. Produce less output. This option can be given multiple times to produce less and less output.
This option results in nontabular output format and escaping of special characters. Escaping may be disabled by using raw mode; see the description for the
--raw
option.Do not write column names in results.
Do not write line numbers for errors. Useful when you want to compare result files that include error messages.
--socket=
,path
-S
path
For connections to
localhost
, the Unix socket file to use, or, on Windows, the name of the named pipe to use.Options that begin with
--ssl
specify whether to connect to the server using SSL and indicate where to find SSL keys and certificates. See Section 5.5.8.3, “SSL Command Options”.--table
,-t
Display output in table format. This is the default for interactive use, but can be used to produce table output in batch mode.
Append a copy of output to the given file. This option works only in interactive mode. Section 4.5.1.2, “mysql Commands”, discusses tee files further.
--unbuffered
,-n
Flush the buffer after each query.
--user=
,user_name
-u
user_name
The MySQL user name to use when connecting to the server.
--verbose
,-v
Verbose mode. Produce more output about what the program does. This option can be given multiple times to produce more and more output. (For example,
-v -v -v
produces table output format even in batch mode.)--version
,-V
Display version information and exit.
--vertical
,-E
Print query output rows vertically (one line per column value). Without this option, you can specify vertical output for individual statements by terminating them with
\G
.--wait
,-w
If the connection cannot be established, wait and retry instead of aborting.
--xml
,-X
Produce XML output.
<field name="
column_name
">NULL</field>The output when
--xml
is used with mysql matches that of mysqldump--xml
. See Section 4.5.4, “mysqldump — A Database Backup Program” for details.The XML output also uses an XML namespace, as shown here:
shell>
mysql --xml -uroot -e "SHOW VARIABLES LIKE 'version%'"
<?xml version="1.0"?> <resultset statement="SHOW VARIABLES LIKE 'version%'" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <row> <field name="Variable_name">version</field> <field name="Value">5.0.40-debug</field> </row> <row> <field name="Variable_name">version_comment</field> <field name="Value">Source distribution</field> </row> <row> <field name="Variable_name">version_compile_machine</field> <field name="Value">i686</field> </row> <row> <field name="Variable_name">version_compile_os</field> <field name="Value">suse-linux-gnu</field> </row> </resultset>(See Bug #25946.)
You can also set the following variables by using
--
.
The var_name
=value
--set-variable
format is deprecated and was
removed in MySQL 5.5.3.
The number of seconds before connection timeout. (Default value is
0
.)The maximum packet length to send to or receive from the server. (Default value is 16MB.)
The automatic limit for rows in a join when using
--safe-updates
. (Default value is 1,000,000.)The buffer size for TCP/IP and socket communication. (Default value is 16KB.)
The automatic limit for
SELECT
statements when using--safe-updates
. (Default value is 1,000.)
mysql sends each SQL statement that you issue
to the server to be executed. There is also a set of commands
that mysql itself interprets. For a list of
these commands, type help
or
\h
at the mysql>
prompt:
mysql> help
List of all MySQL commands:
Note that all text commands must be first on line and end with ';'
? (\?) Synonym for `help'.
clear (\c) Clear command.
connect (\r) Reconnect to the server. Optional arguments are db and host.
delimiter (\d) Set statement delimiter.
edit (\e) Edit command with $EDITOR.
ego (\G) Send command to mysql server, display result vertically.
exit (\q) Exit mysql. Same as quit.
go (\g) Send command to mysql server.
help (\h) Display this help.
nopager (\n) Disable pager, print to stdout.
notee (\t) Don't write into outfile.
pager (\P) Set PAGER [to_pager]. Print the query results via PAGER.
print (\p) Print current command.
prompt (\R) Change your mysql prompt.
quit (\q) Quit mysql.
rehash (\#) Rebuild completion hash.
source (\.) Execute an SQL script file. Takes a file name as an argument.
status (\s) Get status information from the server.
system (\!) Execute a system shell command.
tee (\T) Set outfile [to_outfile]. Append everything into given
outfile.
use (\u) Use another database. Takes database name as argument.
charset (\C) Switch to another charset. Might be needed for processing
binlog with multi-byte charsets.
warnings (\W) Show warnings after every statement.
nowarning (\w) Don't show warnings after every statement.
For server side help, type 'help contents'
Each command has both a long and short form. The long form is not case sensitive; the short form is. The long form can be followed by an optional semicolon terminator, but the short form should not.
The use of short-form commands within multi-line /* ...
*/
comments is not supported.
help [
,arg
]\h [
,arg
]\? [
,arg
]? [
arg
]Display a help message listing the available mysql commands.
If you provide an argument to the
help
command, mysql uses it as a search string to access server-side help from the contents of the MySQL Справочное Руководство. For more information, see Section 4.5.1.4, “mysql Server-Side Help”.charset
,charset_name
\C
charset_name
Change the default character set and issue a
SET NAMES
statement. This enables the character set to remain synchronized on the client and server if mysql is run with auto-reconnect enabled (which is not recommended), because the specified character set is used for reconnects.Clear the current input. Use this if you change your mind about executing the statement that you are entering.
connect [
,db_name
host_name
]]\r [
db_name
host_name
]]Reconnect to the server. The optional database name and host name arguments may be given to specify the default database or the host where the server is running. If omitted, the current values are used.
Change the string that mysql interprets as the separator between SQL statements. The default is the semicolon character (“
;
”).The delimiter string can be specified as an unquoted or quoted argument on the
delimiter
command line. Quoting can be done with either single quote ('
), douple quote ("
), or backtick (`
) characters. To include a quote within a quoted string, either quote the string with a different quote character or escape the quote with a backslash (“\
”) character. Backslash should be avoided outside of quoted strings because it is the escape character for MySQL. For an unquoted argument, the delimiter is read up to the first space or end of line. For a quoted argument, the delimiter is read up to the matching quote on the line.mysql interprets instances of the delimiter string as a statement delimiter anywhere it occurs, except within quoted strings. Be careful about defining a delimiter that might occur within other words. For example, if you define the delimiter as
X
, you will be unable to use the wordINDEX
in statements. mysql interprets this asINDE
followed by the delimiterX
.When the delimiter recognized by mysql is set to something other than the default of “
;
”, instances of that character are sent to the server without interpretation. However, the server itself still interprets “;
” as a statement delimiter and processes statements accordingly. This behavior on the server side comes into play for multiple-statement execution (see Section 21.9.13, “C API Support for Multiple Statement Execution”), and for parsing the body of stored procedures and functions, triggers, and events (see Section 18.1, “Defining Stored Programs”).Edit the current input statement. mysql checks the values of the
EDITOR
andVISUAL
environment variables to determine which editor to use. The default editor is vi if neither variable is set.The
edit
command works only in Unix.Send the current statement to the server to be executed and display the result using vertical format.
Exit mysql.
Send the current statement to the server to be executed.
Disable output paging. See the description for
pager
.The
nopager
command works only in Unix.Disable output copying to the tee file. See the description for
tee
.Enable display of warnings after each statement.
Enable output paging. By using the
--pager
option when you invoke mysql, it is possible to browse or search query results in interactive mode with Unix programs such as less, more, or any other similar program. If you specify no value for the option, mysql checks the value of thePAGER
environment variable and sets the pager to that. Pager functionality works only in interactive mode.Output paging can be enabled interactively with the
pager
command and disabled withnopager
. The command takes an optional argument; if given, the paging program is set to that. With no argument, the pager is set to the pager that was set on the command line, orstdout
if no pager was specified.Output paging works only in Unix because it uses the
popen()
function, which does not exist on Windows. For Windows, thetee
option can be used instead to save query output, although it is not as convenient aspager
for browsing output in some situations.Print the current input statement without executing it.
Reconfigure the mysql prompt to the given string. The special character sequences that can be used in the prompt are described later in this section.
If you specify the
prompt
command with no argument, mysql resets the prompt to the default ofmysql>
.Exit mysql.
Rebuild the completion hash that enables database, table, and column name completion while you are entering statements. (See the description for the
--auto-rehash
option.)source
,file_name
\.
file_name
Read the named file and executes the statements contained therein. On Windows, you can specify path name separators as
/
or\\
.Provide status information about the connection and the server you are using. If you are running in
--safe-updates
mode,status
also prints the values for the mysql variables that affect your queries.Execute the given command using your default command interpreter.
The
system
command works only in Unix.tee [
,file_name
]\T [
file_name
]By using the
--tee
option when you invoke mysql, you can log statements and their output. All the data displayed on the screen is appended into a given file. This can be very useful for debugging purposes also. mysql flushes results to the file after each statement, just before it prints its next prompt. Tee functionality works only in interactive mode.You can enable this feature interactively with the
tee
command. Without a parameter, the previous file is used. Thetee
file can be disabled with thenotee
command. Executingtee
again re-enables logging.Use
db_name
as the default database.Enable display of warnings after each statement (if there are any).
Here are a few tips about the pager
command:
You can use it to write to a file and the results go only to the file:
mysql>
pager cat > /tmp/log.txt
You can also pass any options for the program that you want to use as your pager:
mysql>
pager less -n -i -S
In the preceding example, note the
-S
option. You may find it very useful for browsing wide query results. Sometimes a very wide result set is difficult to read on the screen. The-S
option to less can make the result set much more readable because you can scroll it horizontally using the left-arrow and right-arrow keys. You can also use-S
interactively within less to switch the horizontal-browse mode on and off. For more information, read the less manual page:shell>
man less
The
-F
and-X
options may be used with less to cause it to exit if output fits on one screen, which is convenient when no scrolling is necessary:mysql>
pager less -n -i -S -F -X
You can specify very complex pager commands for handling query output:
mysql>
pager cat | tee /dr1/tmp/res.txt \
| tee /dr2/tmp/res2.txt | less -n -i -S
In this example, the command would send query results to two files in two different directories on two different file systems mounted on
/dr1
and/dr2
, yet still display the results onscreen using less.
You can also combine the tee
and
pager
functions. Have a
tee
file enabled and pager
set to less, and you are able to browse the
results using the less program and still have
everything appended into a file the same time. The difference
between the Unix tee
used with the
pager
command and the
mysql built-in tee
command
is that the built-in tee
works even if you do
not have the Unix tee available. The built-in
tee
also logs everything that is printed on
the screen, whereas the Unix tee used with
pager
does not log quite that much.
Additionally, tee
file logging can be turned
on and off interactively from within mysql.
This is useful when you want to log some queries to a file, but
not others.
The prompt
command reconfigures the default
mysql>
prompt. The string for defining the
prompt can contain the following special sequences.
Option | Описание |
---|---|
\c | A counter that increments for each statement you issue |
\D | The full current date |
\d | The default database |
\h | The server host |
\l | The current delimiter |
\m | Minutes of the current time |
\n | A newline character |
\O | The current month in three-letter format (Jan, Feb, …) |
\o | The current month in numeric format |
\P | am/pm |
\p | The current TCP/IP port or socket file |
\R | The current time, in 24-hour military time (0–23) |
\r | The current time, standard 12-hour time (1–12) |
\S | Semicolon |
\s | Seconds of the current time |
\t | A tab character |
\U |
Your full
|
\u | Your user name |
\v | The server version |
\w | The current day of the week in three-letter format (Mon, Tue, …) |
\Y | The current year, four digits |
\y | The current year, two digits |
\_ | A space |
\ | A space (a space follows the backslash) |
\' | Single quote |
\" | Double quote |
\\ | A literal “\ ” backslash character |
\ |
|
You can set the prompt in several ways:
Use an environment variable. You can set the
MYSQL_PS1
environment variable to a prompt string. For example:shell>
export MYSQL_PS1="(\u@\h) [\d]> "
Use a command-line option. You can set the
--prompt
option on the command line to mysql. For example:shell>
mysql --prompt="(\u@\h) [\d]> "
(user@host) [database]>Use an option file. You can set the
prompt
option in the[mysql]
group of any MySQL option file, such as/etc/my.cnf
or the.my.cnf
file in your home directory. For example:[mysql] prompt=(\\u@\\h) [\\d]>\\_
In this example, note that the backslashes are doubled. If you set the prompt using the
prompt
option in an option file, it is advisable to double the backslashes when using the special prompt options. There is some overlap in the set of permissible prompt options and the set of special escape sequences that are recognized in option files. (The rules for escape sequences in option files are listed in Section 4.2.3.3, “Using Option Files”.) The overlap may cause you problems if you use single backslashes. For example,\s
is interpreted as a space rather than as the current seconds value. The following example shows how to define a prompt within an option file to include the current time inHH:MM:SS>
format:[mysql] prompt="\\r:\\m:\\s> "
Set the prompt interactively. You can change your prompt interactively by using the
prompt
(or\R
) command. For example:mysql>
prompt (\u@\h) [\d]>\_
PROMPT set to '(\u@\h) [\d]>\_' (user
@host
) [database
]> (user
@host
) [database
]> prompt Returning to default PROMPT of mysql> mysql>
On Unix, the mysql client writes a record of
executed statements to a history file. By default, this file is
named .mysql_history
and is created in your
home directory. To specify a different file, set the value of
the MYSQL_HISTFILE
environment variable.
The .mysql_history
should be protected with
a restrictive access mode because sensitive information might be
written to it, such as the text of SQL statements that contain
passwords. See Section 5.3.2.2, “End-User Guidelines for Password Security”.
It is possible to suppress logging of statements to the history
file by using the --batch
or
--execute
option.
If you do not want to maintain a history file, first remove
.mysql_history
if it exists, and then use
either of the following techniques:
Set the
MYSQL_HISTFILE
variable to/dev/null
. To cause this setting to take effect each time you log in, put the setting in one of your shell's startup files.Create
.mysql_history
as a symbolic link to/dev/null
:shell>
ln -s /dev/null $HOME/.mysql_history
You need do this only once.
mysql> help search_string
If you provide an argument to the help
command, mysql uses it as a search string to
access server-side help from the contents of the MySQL Reference
Manual. The proper operation of this command requires that the
help tables in the mysql
database be
initialized with help topic information (see
Section 5.1.8, “Server-Side Help”).
If there is no match for the search string, the search fails:
mysql> help me
Nothing found
Please try to run 'help contents' for a list of all accessible topics
Use help contents to see a list of the help categories:
mysql> help contents
You asked for help about help category: "Contents"
For more information, type 'help <item>', where <item> is one of the
following categories:
Account Management
Administration
Data Definition
Data Manipulation
Data Types
Functions
Functions and Modifiers for Use with GROUP BY
Geographic Features
Language Structure
Plugins
Storage Engines
Stored Routines
Table Maintenance
Transactions
Triggers
If the search string matches multiple items, mysql shows a list of matching topics:
mysql> help logs
Many help items for your request exist.
To make a more specific request, please type 'help <item>',
where <item> is one of the following topics:
SHOW
SHOW BINARY LOGS
SHOW ENGINE
SHOW LOGS
Use a topic as the search string to see the help entry for that topic:
mysql> help show binary logs
Name: 'SHOW BINARY LOGS'
Описание:
Syntax:
SHOW BINARY LOGS
SHOW MASTER LOGS
Lists the binary log files on the server. This statement is used as
part of the procedure described in [purge-binary-logs], that shows how
to determine which logs can be purged.
mysql> SHOW BINARY LOGS;
+---------------+-----------+
| Log_name | File_size |
+---------------+-----------+
| binlog.000015 | 724935 |
| binlog.000016 | 733481 |
+---------------+-----------+
The mysql client typically is used interactively, like this:
shell> mysql db_name
However, it is also possible to put your SQL statements in a
file and then tell mysql to read its input
from that file. To do so, create a text file
text_file
that contains the
statements you wish to execute. Then invoke
mysql as shown here:
shell> mysql db_name
< text_file
If you place a USE
statement as the
first statement in the file, it is unnecessary to specify the
database name on the command line:
db_name
shell> mysql < text_file
If you are already running mysql, you can
execute an SQL script file using the source
command or \.
command:
mysql>source
mysql>file_name
\.
file_name
Sometimes you may want your script to display progress information to the user. For this you can insert statements like this:
SELECT '<info_to_display>' AS ' ';
The statement shown outputs
<info_to_display>
.
You can also invoke mysql with the
--verbose
option, which causes
each statement to be displayed before the result that it
produces.
mysql ignores Unicode byte order mark (BOM)
characters at the beginning of input files. Previously, it read
them and sent them to the server, resulting in a syntax error.
Presence of a BOM does not cause mysql to
change its default character set. To do that, invoke
mysql with an option such as
--default-character-set=utf8
.
For more information about batch mode, see Section 3.5, “Using mysql in Batch Mode”.
This section describes some techniques that can help you use mysql more effectively.
Some query results are much more readable when displayed vertically, instead of in the usual horizontal table format. Queries can be displayed vertically by terminating the query with \G instead of a semicolon. For example, longer text values that include newlines often are much easier to read with vertical output:
mysql> SELECT * FROM mails WHERE LENGTH(txt) < 300 LIMIT 300,1\G
*************************** 1. row ***************************
msg_nro: 3068
date: 2000-03-01 23:29:50
time_zone: +0200
mail_from: Monty
reply: monty@no.spam.com
mail_to: "Thimble Smith" <tim@no.spam.com>
sbj: UTF-8
txt: >>>>> "Thimble" == Thimble Smith writes:
Thimble> Hi. I think this is a good idea. Is anyone familiar
Thimble> with UTF-8 or Unicode? Otherwise, I'll put this on my
Thimble> TODO list and see what happens.
Yes, please do that.
Regards,
Monty
file: inbox-jani-1
hash: 190402944
1 row in set (0.09 sec)
4.5.1.6.2. Using the --safe-updates
Option
For beginners, a useful startup option is
--safe-updates
(or
--i-am-a-dummy
,
which has the same effect). It is helpful for cases when you
might have issued a DELETE FROM
statement but
forgotten the tbl_name
WHERE
clause. Normally, such
a statement deletes all rows from the table. With
--safe-updates
, you can delete
rows only by specifying the key values that identify them.
This helps prevent accidents.
When you use the --safe-updates
option, mysql issues the following
statement when it connects to the MySQL server:
SET sql_safe_updates=1, sql_select_limit=1000, sql_max_join_size=1000000;
See Section 5.1.3, “Server System Variables”.
The
SET
statement has the following effects:
You are not permitted to execute an
UPDATE
orDELETE
statement unless you specify a key constraint in theWHERE
clause or provide aLIMIT
clause (or both). For example:UPDATE
tbl_name
SETnot_key_column
=val
WHEREkey_column
=val
; UPDATEtbl_name
SETnot_key_column
=val
LIMIT 1;The server limits all large
SELECT
results to 1,000 rows unless the statement includes aLIMIT
clause.The server aborts multiple-table
SELECT
statements that probably need to examine more than 1,000,000 row combinations.
To specify limits different from 1,000 and 1,000,000, you can
override the defaults by using the
--select_limit
and
--max_join_size
options:
shell> mysql --safe-updates --select_limit=500 --max_join_size=10000
If the mysql client loses its connection to the server while sending a statement, it immediately and automatically tries to reconnect once to the server and send the statement again. However, even if mysql succeeds in reconnecting, your first connection has ended and all your previous session objects and settings are lost: temporary tables, the autocommit mode, and user-defined and session variables. Also, any current transaction rolls back. This behavior may be dangerous for you, as in the following example where the server was shut down and restarted between the first and second statements without you knowing it:
mysql>SET @a=1;
Query OK, 0 rows affected (0.05 sec) mysql>INSERT INTO t VALUES(@a);
ERROR 2006: MySQL server has gone away No connection. Trying to reconnect... Connection id: 1 Current database: test Query OK, 1 row affected (1.30 sec) mysql>SELECT * FROM t;
+------+ | a | +------+ | NULL | +------+ 1 row in set (0.05 sec)
The @a
user variable has been lost with the
connection, and after the reconnection it is undefined. If it
is important to have mysql terminate with
an error if the connection has been lost, you can start the
mysql client with the
--skip-reconnect
option.
For more information about auto-reconnect and its effect on state information when a reconnection occurs, see Section 21.9.12, “Controlling Automatic Reconnection Behavior”.
mysqladmin is a client for performing administrative operations. You can use it to check the server's configuration and current status, to create and drop databases, and more.
Invoke mysqladmin like this:
shell> mysqladmin [options
] command
[command-arg
] [command
[command-arg
]] ...
mysqladmin supports the following commands. Some of the commands take an argument following the command name.
Create a new database named
db_name
.Tell the server to write debug information to the error log.
This includes information about the Event Scheduler. See Section 18.4.5, “Event Scheduler Status”.
Delete the database named
db_name
and all its tables.Display the server status variables and their values.
Flush all information in the host cache.
Flush all logs.
Reload the grant tables (same as
reload
).Clear status variables.
Flush all tables.
Flush the thread cache.
Kill server threads. If multiple thread ID values are given, there must be no spaces in the list.
This is like the
password
command but stores the password using the old (pre-4.1) password-hashing format. (See Section 5.3.2.3, “Password Hashing in MySQL”.)Set a new password. This changes the password to
new-password
for the account that you use with mysqladmin for connecting to the server. Thus, the next time you invoke mysqladmin (or any other client program) using the same account, you will need to specify the new password.If the
new-password
value contains spaces or other characters that are special to your command interpreter, you need to enclose it within quotation marks. On Windows, be sure to use double quotation marks rather than single quotation marks; single quotation marks are not stripped from the password, but rather are interpreted as part of the password. For example:shell>
mysqladmin password "my new password"
As of MySQL 5.5.3, the new password can be omitted following the
password
command. In this case, mysqladmin prompts for the password value, which enables you to avoid specifying the password on the command line. Omitting the password value should be done only ifpassword
is the final command on the mysqladmin command line. Otherwise, the next argument is taken as the password.CautionDo not use this command used if the server was started with the
--skip-grant-tables
option. No password change will be applied. This is true even if you precede thepassword
command withflush-privileges
on the same command line to re-enable the grant tables because the flush operation occurs after you connect. However, you can use mysqladmin flush-privileges to re-enable the grant table and then use a separate mysqladmin password command to change the password.Check whether the server is available. The return status from mysqladmin is 0 if the server is running, 1 if it is not. This is 0 even in case of an error such as
Access denied
, because this means that the server is running but refused the connection, which is different from the server not running.Show a list of active server threads. This is like the output of the
SHOW PROCESSLIST
statement. If the--verbose
option is given, the output is like that ofSHOW FULL PROCESSLIST
. (See Section 12.7.5.30, “SHOW PROCESSLIST
Синтаксис”.)Reload the grant tables.
Flush all tables and close and open log files.
Stop the server.
Start replication on a slave server.
Display a short server status message.
Stop replication on a slave server.
Display the server system variables and their values.
Display version information from the server.
All commands can be shortened to any unique prefix. For example:
shell> mysqladmin proc stat
+----+-------+-----------+----+---------+------+-------+------------------+
| Id | User | Host | db | Command | Time | State | Info |
+----+-------+-----------+----+---------+------+-------+------------------+
| 51 | monty | localhost | | Query | 0 | | show processlist |
+----+-------+-----------+----+---------+------+-------+------------------+
Uptime: 1473624 Threads: 1 Questions: 39487
Slow queries: 0 Opens: 541 Flush tables: 1
Open tables: 19 Queries per second avg: 0.0268
The mysqladmin status command result displays the following values:
The number of seconds the MySQL server has been running.
The number of active threads (clients).
The number of questions (queries) from clients since the server was started.
The number of queries that have taken more than
long_query_time
seconds. See Section 5.2.5, “The Slow Query Log”.The number of tables the server has opened.
The number of
flush-*
,refresh
, andreload
commands the server has executed.The number of tables that currently are open.
The amount of memory allocated directly by mysqld. This value is displayed only when MySQL has been compiled with
safemalloc
, which is available only before MySQL 5.5.6.The maximum amount of memory allocated directly by mysqld. This value is displayed only when MySQL has been compiled with
safemalloc
, which is available only before MySQL 5.5.6.
If you execute mysqladmin shutdown when connecting to a local server using a Unix socket file, mysqladmin waits until the server's process ID file has been removed, to ensure that the server has stopped properly.
mysqladmin supports the following options,
which can be specified on the command line or in the
[mysqladmin]
and [client]
groups of an option file. mysqladmin also
supports the options for processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
Table 4.3. mysqladmin
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--compress | compress | Compress all information sent between the client and the server | |||
--connect_timeout=seconds | connect_timeout | The number of seconds before connection timeout | |||
--count=# | count | The number of iterations to make for repeated command execution | |||
--debug[=debug_options] | debug | Write a debugging log | |||
--debug-check | debug-check | Print debugging information when the program exits | |||
--debug-info | debug-info | Print debugging information, memory and CPU statistics when the program exits | |||
--default-auth=plugin | default-auth=plugin | The authentication plugin to use | 5.5.9 | ||
--default-character-set=charset_name | default-character-set | Use charset_name as the default character set | |||
--force | force | Continue even if an SQL error occurs | |||
--help | Display help message and exit | ||||
--host=host_name | host | Connect to the MySQL server on the given host | |||
--no-beep | no-beep | Do not beep when errors occur | |||
--password[=password] | password | The password to use when connecting to the server | |||
--pipe | On Windows, connect to server using a named pipe | ||||
--plugin-dir=path | plugin-dir=path | The directory where plugins are located | 5.5.9 | ||
--port=port_num | port | The TCP/IP port number to use for the connection | |||
--protocol=type | protocol | The connection protocol to use | |||
--relative | relative | Show the difference between the current and previous values when used with the --sleep option | |||
--shutdown_timeout=seconds | shutdown_timeout | The maximum number of seconds to wait for server shutdown | |||
--silent | silent | Silent mode | |||
--sleep=delay | sleep | Execute commands repeatedly, sleeping for delay seconds in between | |||
--socket=path | socket | For connections to localhost | |||
--ssl-ca=file_name | ssl-ca | The path to a file that contains a list of trusted SSL CAs | |||
--ssl-capath=dir_name | ssl-capath | The path to a directory that contains trusted SSL CA certificates in PEM format | |||
--ssl-cert=file_name | ssl-cert | The name of the SSL certificate file to use for establishing a secure connection | |||
--ssl-cipher=cipher_list | ssl-cipher | A list of allowable ciphers to use for SSL encryption | |||
--ssl-key=file_name | ssl-key | The name of the SSL key file to use for establishing a secure connection | |||
--ssl-verify-server-cert | ssl-verify-server-cert | The server's Common Name value in its certificate is verified against the host name used when connecting to the server | |||
--user=user_name, | user | The MySQL user name to use when connecting to the server | |||
--verbose | Verbose mode | ||||
--version | Display version information and exit | ||||
--vertical | vertical | Print query output rows vertically (one line per column value) | |||
--wait | wait | If the connection cannot be established, wait and retry instead of aborting |
--help
,-?
Display a help message and exit.
On a computer having multiple network interfaces, this option can be used to select which interface is employed when connecting to the MySQL server.
This option is supported only in the version of mysqladmin that is supplied with MySQL Cluster. It is not available in standard MySQL Server 5.5 releases.
The directory where character sets are installed. See Section 9.5, “Character Set Configuration”.
--compress
,-C
Compress all information sent between the client and the server if both support compression.
--count=
,N
-c
N
The number of iterations to make for repeated command execution if the
--sleep
option is given.--debug[=
,debug_options
]-# [
debug_options
]Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default isfile_name
''d:t:o,/tmp/mysqladmin.trace'
.Print some debugging information when the program exits.
Print debugging information and memory and CPU usage statistics when the program exits.
The client-side authentication plugin to use. See Section 5.5.6, “Pluggable Authentication”.
This option was added in MySQL 5.5.9.
--default-character-set=
charset_name
Use
charset_name
as the default character set. See Section 9.5, “Character Set Configuration”.--force
,-f
Do not ask for confirmation for the
drop
command. With multiple commands, continue even if an error occurs.db_name
--host=
,host_name
-h
host_name
Connect to the MySQL server on the given host.
--no-beep
,-b
Suppress the warning beep that is emitted by default for errors such as a failure to connect to the server.
--password[=
,password
]-p[
password
]The password to use when connecting to the server. If you use the short option form (
-p
), you cannot have a space between the option and the password. If you omit thepassword
value following the--password
or-p
option on the command line, mysqladmin prompts for one.Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
--pipe
,-W
On Windows, connect to the server using a named pipe. This option applies only if the server supports named-pipe connections.
The directory in which to look for plugins. It may be necessary to specify this option if the
--default-auth
option is used to specify an authentication plugin but mysqladmin does not find it. See Section 5.5.6, “Pluggable Authentication”.This option was added in MySQL 5.5.9.
--port=
,port_num
-P
port_num
The TCP/IP port number to use for the connection.
--protocol={TCP|SOCKET|PIPE|MEMORY}
The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the permissible values, see Section 4.2.2, “Connecting to the MySQL Server”.
--relative
,-r
Show the difference between the current and previous values when used with the
--sleep
option. This option works only with theextended-status
command.--silent
,-s
Exit silently if a connection to the server cannot be established.
--sleep=
,delay
-i
delay
Execute commands repeatedly, sleeping for
delay
seconds in between. The--count
option determines the number of iterations. If--count
is not given, mysqladmin executes commands indefinitely until interrupted.--socket=
,path
-S
path
For connections to
localhost
, the Unix socket file to use, or, on Windows, the name of the named pipe to use.Options that begin with
--ssl
specify whether to connect to the server using SSL and indicate where to find SSL keys and certificates. See Section 5.5.8.3, “SSL Command Options”.--user=
,user_name
-u
user_name
The MySQL user name to use when connecting to the server.
--verbose
,-v
Verbose mode. Print more information about what the program does.
--version
,-V
Display version information and exit.
--vertical
,-E
Print output vertically. This is similar to
--relative
, but prints output vertically.--wait[=
,count
]-w[
count
]If the connection cannot be established, wait and retry instead of aborting. If a
count
value is given, it indicates the number of times to retry. The default is one time.
You can also set the following variables by using
--
The var_name
=value
--set-variable
format is deprecated and was
removed in MySQL 5.5.3. syntax:
The mysqlcheck client performs table maintenance: It checks, repairs, optimizes, or analyzes tables.
Each table is locked and therefore unavailable to other sessions
while it is being processed, although for check operations, the
table is locked with a READ
lock only (see
Section 12.3.5, “LOCK TABLES
and
UNLOCK
TABLES
Синтаксис”, for more information about
READ
and WRITE
locks).
Table maintenance operations can be time-consuming, particularly
for large tables. If you use the
--databases
or
--all-databases
option to
process all tables in one or more databases, an invocation of
mysqlcheck might take a long time. (This is
also true for mysql_upgrade because that
program invokes mysqlcheck to check all
tables and repair them if necessary.)
mysqlcheck is similar in function to myisamchk, but works differently. The main operational difference is that mysqlcheck must be used when the mysqld server is running, whereas myisamchk should be used when it is not. The benefit of using mysqlcheck is that you do not have to stop the server to perform table maintenance.
mysqlcheck uses the SQL statements
CHECK TABLE
,
REPAIR TABLE
,
ANALYZE TABLE
, and
OPTIMIZE TABLE
in a convenient
way for the user. It determines which statements to use for the
operation you want to perform, and then sends the statements to
the server to be executed. For details about which storage
engines each statement works with, see the descriptions for
those statements in Section 12.7.2, “Table Maintenance Statements”.
The MyISAM
storage engine supports all four
maintenance operations, so mysqlcheck can be
used to perform any of them on MyISAM
tables.
Other storage engines do not necessarily support all operations.
In such cases, an error message is displayed. For example, if
test.t
is a MEMORY
table,
an attempt to check it produces this result:
shell> mysqlcheck test t
test.t
note : The storage engine for the table doesn't support check
If mysqlcheck is unable to repair a table,
see Section 2.11.4, “Rebuilding or Repairing Tables or Indexes” for manual table repair
strategies. This will be the case, for example, for
InnoDB
tables, which can be checked with
CHECK TABLE
, but not repaired
with REPAIR TABLE
.
It is best to make a backup of a table before performing a table repair operation; under some circumstances the operation might cause data loss. Possible causes include but are not limited to file system errors.
There are three general ways to invoke mysqlcheck:
shell>mysqlcheck [
shell>options
]db_name
[tbl_name
...]mysqlcheck [
shell>options
] --databasesdb_name
...mysqlcheck [
options
] --all-databases
If you do not name any tables following
db_name
or if you use the
--databases
or
--all-databases
option,
entire databases are checked.
mysqlcheck has a special feature compared to
other client programs. The default behavior of checking tables
(--check
) can be changed by
renaming the binary. If you want to have a tool that repairs
tables by default, you should just make a copy of
mysqlcheck named
mysqlrepair, or make a symbolic link to
mysqlcheck named
mysqlrepair. If you invoke
mysqlrepair, it repairs tables.
The names shown in the following table can be used to change mysqlcheck default behavior.
Command | Meaning |
---|---|
mysqlrepair | The default option is --repair |
mysqlanalyze | The default option is --analyze |
mysqloptimize | The default option is --optimize |
mysqlcheck supports the following options,
which can be specified on the command line or in the
[mysqlcheck]
and [client]
groups of an option file. mysqlcheck also
supports the options for processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
Table 4.4. mysqlcheck
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--all-databases | all-databases | Check all tables in all databases | |||
--all-in-1 | all-in-1 | Execute a single statement for each database that names all the tables from that database | |||
--analyze | analyze | Analyze the tables | |||
--auto-repair | auto-repair | If a checked table is corrupted, automatically fix it | |||
--character-sets-dir=path | character-sets-dir | The directory where character sets are installed | |||
--check | check | Check the tables for errors | |||
--check-only-changed | check-only-changed | Check only tables that have changed since the last check | |||
--check-upgrade | check-upgrade | Invoke CHECK TABLE with the FOR UPGRADE option | |||
--compress | compress | Compress all information sent between the client and the server | |||
--databases | databases | Process all tables in the named databases | |||
--debug[=debug_options] | debug | Write a debugging log | |||
--debug-check | debug-check | Print debugging information when the program exits | |||
--debug-info | debug-info | Print debugging information, memory and CPU statistics when the program exits | |||
--default-auth=plugin | default-auth=plugin | The authentication plugin to use | 5.5.10 | ||
--default-character-set=charset_name | default-character-set | Use charset_name as the default character set | |||
--extended | extended | Check and repair tables | |||
--fast | fast | Check only tables that have not been closed properly | |||
--fix-db-names | fix-db-names | Convert database names to 5.1 format | |||
--fix-table-names | fix-table-names | Convert table names to 5.1 format | |||
--force | force | Continue even if an SQL error occurs | |||
--help | Display help message and exit | ||||
--host=host_name | host | Connect to the MySQL server on the given host | |||
--medium-check | medium-check | Do a check that is faster than an --extended operation | |||
--optimize | optimize | Optimize the tables | |||
--password[=password] | password | The password to use when connecting to the server | |||
--pipe | On Windows, connect to server using a named pipe | ||||
--plugin-dir=path | plugin-dir=path | The directory where plugins are located | 5.5.10 | ||
--port=port_num | port | The TCP/IP port number to use for the connection | |||
--protocol=type | protocol | The connection protocol to use | |||
--quick | quick | The fastest method of checking | |||
--repair | repair | Perform a repair that can fix almost anything except unique keys that are not unique | |||
--silent | silent | Silent mode | |||
--socket=path | socket | For connections to localhost | |||
--ssl-ca=file_name | ssl-ca | The path to a file that contains a list of trusted SSL CAs | |||
--ssl-capath=dir_name | ssl-capath | The path to a directory that contains trusted SSL CA certificates in PEM format | |||
--ssl-cert=file_name | ssl-cert | The name of the SSL certificate file to use for establishing a secure connection | |||
--ssl-cipher=cipher_list | ssl-cipher | A list of allowable ciphers to use for SSL encryption | |||
--ssl-key=file_name | ssl-key | The name of the SSL key file to use for establishing a secure connection | |||
--ssl-verify-server-cert | ssl-verify-server-cert | The server's Common Name value in its certificate is verified against the host name used when connecting to the server | |||
--tables | tables | Overrides the --databases or -B option | |||
--use-frm | use-frm | For repair operations on MyISAM tables | |||
--user=user_name, | user | The MySQL user name to use when connecting to the server | |||
--verbose | Verbose mode | ||||
--version | Display version information and exit | ||||
--write-binlog | write-binlog | Log ANALYZE, OPTIMIZE, REPAIR statements to binary log. --skip-write-binlog adds NO_WRITE_TO_BINLOG to these statements. |
--help
,-?
Display a help message and exit.
--all-databases
,-A
Check all tables in all databases. This is the same as using the
--databases
option and naming all the databases on the command line.--all-in-1
,-1
Instead of issuing a statement for each table, execute a single statement for each database that names all the tables from that database to be processed.
--analyze
,-a
Analyze the tables.
If a checked table is corrupted, automatically fix it. Any necessary repairs are done after all tables have been checked.
On a computer having multiple network interfaces, this option can be used to select which interface is employed when connecting to the MySQL server.
This option is supported only in the version of mysqlcheck that is supplied with MySQL Cluster. It is not available in standard MySQL Server 5.5 releases.
The directory where character sets are installed. See Section 9.5, “Character Set Configuration”.
--check
,-c
Check the tables for errors. This is the default operation.
Check only tables that have changed since the last check or that have not been closed properly.
--check-upgrade
,-g
Invoke
CHECK TABLE
with theFOR UPGRADE
option to check tables for incompatibilities with the current version of the server. This option automatically enables the--fix-db-names
and--fix-table-names
options.Compress all information sent between the client and the server if both support compression.
--databases
,-B
Process all tables in the named databases. Normally, mysqlcheck treats the first name argument on the command line as a database name and following names as table names. With this option, it treats all name arguments as database names.
--debug[=
,debug_options
]-# [
debug_options
]Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default isfile_name
''d:t:o'
.Print some debugging information when the program exits.
Print debugging information and memory and CPU usage statistics when the program exits.
--default-character-set=
charset_name
Use
charset_name
as the default character set. See Section 9.5, “Character Set Configuration”.--extended
,-e
If you are using this option to check tables, it ensures that they are 100% consistent but takes a long time.
If you are using this option to repair tables, it runs an extended repair that may not only take a long time to execute, but may produce a lot of garbage rows also!
The client-side authentication plugin to use. See Section 5.5.6, “Pluggable Authentication”.
This option was added in MySQL 5.5.10.
--fast
,-F
Check only tables that have not been closed properly.
Convert database names to 5.1 format. Only database names that contain special characters are affected.
Convert table names to 5.1 format. Only table names that contain special characters are affected. This option also applies to views.
--force
,-f
Continue even if an SQL error occurs.
--host=
,host_name
-h
host_name
Connect to the MySQL server on the given host.
--medium-check
,-m
Do a check that is faster than an
--extended
operation. This finds only 99.99% of all errors, which should be good enough in most cases.--optimize
,-o
Optimize the tables.
--password[=
,password
]-p[
password
]The password to use when connecting to the server. If you use the short option form (
-p
), you cannot have a space between the option and the password. If you omit thepassword
value following the--password
or-p
option on the command line, mysqlcheck prompts for one.Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
--pipe
,-W
On Windows, connect to the server using a named pipe. This option applies only if the server supports named-pipe connections.
The directory in which to look for plugins. It may be necessary to specify this option if the
--default-auth
option is used to specify an authentication plugin but mysqlcheck does not find it. See Section 5.5.6, “Pluggable Authentication”.This option was added in MySQL 5.5.10.
--port=
,port_num
-P
port_num
The TCP/IP port number to use for the connection.
--protocol={TCP|SOCKET|PIPE|MEMORY}
The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the permissible values, see Section 4.2.2, “Connecting to the MySQL Server”.
--quick
,-q
If you are using this option to check tables, it prevents the check from scanning the rows to check for incorrect links. This is the fastest check method.
If you are using this option to repair tables, it tries to repair only the index tree. This is the fastest repair method.
--repair
,-r
Perform a repair that can fix almost anything except unique keys that are not unique.
--silent
,-s
Silent mode. Print only error messages.
--socket=
,path
-S
path
For connections to
localhost
, the Unix socket file to use, or, on Windows, the name of the named pipe to use.Options that begin with
--ssl
specify whether to connect to the server using SSL and indicate where to find SSL keys and certificates. See Section 5.5.8.3, “SSL Command Options”.Override the
--databases
or-B
option. All name arguments following the option are regarded as table names.For repair operations on
MyISAM
tables, get the table structure from the.frm
file so that the table can be repaired even if the.MYI
header is corrupted.--user=
,user_name
-u
user_name
The MySQL user name to use when connecting to the server.
--verbose
,-v
Verbose mode. Print information about the various stages of program operation.
--version
,-V
Display version information and exit.
This option is enabled by default, so that
ANALYZE TABLE
,OPTIMIZE TABLE
, andREPAIR TABLE
statements generated by mysqlcheck are written to the binary log. Use--skip-write-binlog
to causeNO_WRITE_TO_BINLOG
to be added to the statements so that they are not logged. Use the--skip-write-binlog
when these statements should not be sent to replication slaves or run when using the binary logs for recovery from backup.
The mysqldump client is a backup program originally written by Igor Romanenko. It can be used to dump a database or a collection of databases for backup or transfer to another SQL server (not necessarily a MySQL server). The dump typically contains SQL statements to create the table, populate it, or both. However, mysqldump can also be used to generate files in CSV, other delimited text, or XML format.
If you are doing a backup on the server and your tables all are
MyISAM
tables, consider using the
mysqlhotcopy instead because it can
accomplish faster backups and faster restores. See
Section 4.6.9, “mysqlhotcopy — A Database Backup Program”.
There are three general ways to invoke mysqldump:
shell>mysqldump [
shell>options
]db_name
[tbl_name
...]mysqldump [
shell>options
] --databasesdb_name
...mysqldump [
options
] --all-databases
If you do not name any tables following
db_name
or if you use the
--databases
or
--all-databases
option, entire
databases are dumped.
mysqldump does not dump the
INFORMATION_SCHEMA
database by default.
mysqldump dumps
INFORMATION_SCHEMA
only if you name it
explicitly on the command line, although currently you must also
use the
--skip-lock-tables
option. Before MySQL 5.5
mysqldump silently ignores
INFORMATION_SCHEMA
even if you name it
explicitly on the command line.
mysqldump does not dump the
performance_schema
database.
mysqldump also does not dump the MySQL
Cluster ndbinfo
information database.
To see a list of the options your version of mysqldump supports, execute mysqldump --help.
Some mysqldump options are shorthand for groups of other options:
Use of
--opt
is the same as specifying--add-drop-table
,--add-locks
,--create-options
,--disable-keys
,--extended-insert
,--lock-tables
,--quick
, and--set-charset
. All of the options that--opt
stands for also are on by default because--opt
is on by default.Use of
--compact
is the same as specifying--skip-add-drop-table
,--skip-add-locks
,--skip-comments
,--skip-disable-keys
, and--skip-set-charset
options.
To reverse the effect of a group option, uses its
--skip-
form
(xxx
--skip-opt
or
--skip-compact
).
It is also possible to select only part of the effect of a group
option by following it with options that enable or disable
specific features. Here are some examples:
To select the effect of
--opt
except for some features, use the--skip
option for each feature. To disable extended inserts and memory buffering, use--opt
--skip-extended-insert
--skip-quick
. (Actually,--skip-extended-insert
--skip-quick
is sufficient because--opt
is on by default.)To reverse
--opt
for all features except index disabling and table locking, use--skip-opt
--disable-keys
--lock-tables
.
When you selectively enable or disable the effect of a group
option, order is important because options are processed first
to last. For example,
--disable-keys
--lock-tables
--skip-opt
would not have the
intended effect; it is the same as
--skip-opt
by itself.
mysqldump can retrieve and dump table
contents row by row, or it can retrieve the entire content from
a table and buffer it in memory before dumping it. Buffering in
memory can be a problem if you are dumping large tables. To dump
tables row by row, use the
--quick
option (or
--opt
, which enables
--quick
). The
--opt
option (and hence
--quick
) is enabled by
default, so to enable memory buffering, use
--skip-quick
.
If you are using a recent version of
mysqldump to generate a dump to be reloaded
into a very old MySQL server, you should not use the
--opt
or
--extended-insert
option. Use
--skip-opt
instead.
For additional information about mysqldump, see Section 6.4, “Using mysqldump for Backups”.
mysqldump supports the following options,
which can be specified on the command line or in the
[mysqldump]
and [client]
groups of an option file. mysqldump also
supports the options for processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
Table 4.5. mysqldump
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--add-drop-database | add-drop-database | Add a DROP DATABASE statement before each CREATE DATABASE statement | |||
--add-drop-table | add-drop-table | Add a DROP TABLE statement before each CREATE TABLE statement | |||
--add-locks | add-locks | Surround each table dump with LOCK TABLES and UNLOCK TABLES statements | |||
--all-databases | all-databases | Dump all tables in all databases | |||
--allow-keywords | allow-keywords | Allow creation of column names that are keywords | |||
--apply-slave-statements | apply-slave-statements | Include STOP SLAVE prior to CHANGE MASTER statement and START SLAVE at end of output | 5.5.3 | ||
--bind-address=ip_address | bind-address | Use the specified network interface to connect to the MySQL Server | 5.5.8 | ||
--comments | comments | Add comments to the dump file | |||
--compact | compact | Produce more compact output | |||
--compatible=name[,name,...] | compatible | Produce output that is more compatible with other database systems or with older MySQL servers | |||
--complete-insert | complete-insert | Use complete INSERT statements that include column names | |||
--create-options | create-options | Include all MySQL-specific table options in CREATE TABLE statements | |||
--databases | databases | Dump several databases | |||
--debug[=debug_options] | debug | Write a debugging log | |||
--debug-check | debug-check | Print debugging information when the program exits | |||
--debug-info | debug-info | Print debugging information, memory and CPU statistics when the program exits | |||
--default-auth=plugin | default-auth=plugin | The authentication plugin to use | 5.5.9 | ||
--default-character-set=charset_name | default-character-set | Use charset_name as the default character set | |||
--delayed-insert | delayed-insert | Write INSERT DELAYED statements rather than INSERT statements | |||
--delete-master-logs | delete-master-logs | On a master replication server, delete the binary logs after performing the dump operation | |||
--disable-keys | disable-keys | For each table, surround the INSERT statements with statements to disable and enable keys | |||
--dump-date | dump-date | Include dump date as "Dump completed on" comment if --comments is given | |||
--dump-slave[=value] | dump-slave | Include CHANGE MASTER statement that lists binary log coordinates of slave's master | 5.5.3 | ||
--events | events | Dump events from the dumped databases | |||
--extended-insert | extended-insert | Use multiple-row INSERT syntax that include several VALUES lists | |||
--fields-enclosed-by=string | fields-enclosed-by | This option is used with the --tab option and has the same meaning as the corresponding clause for LOAD DATA INFILE | |||
--fields-escaped-by | fields-escaped-by | This option is used with the --tab option and has the same meaning as the corresponding clause for LOAD DATA INFILE | |||
--fields-optionally-enclosed-by=string | fields-optionally-enclosed-by | This option is used with the --tab option and has the same meaning as the corresponding clause for LOAD DATA INFILE | |||
--fields-terminated-by=string | fields-terminated-by | This option is used with the --tab option and has the same meaning as the corresponding clause for LOAD DATA INFILE | |||
--first-slave | first-slave | Deprecated; use --lock-all-tables instead | 5.5.3 | ||
--flush-logs | flush-logs | Flush the MySQL server log files before starting the dump | |||
--flush-privileges | flush-privileges | Emit a FLUSH PRIVILEGES statement after dumping the mysql database | |||
--help | Display help message and exit | ||||
--hex-blob | hex-blob | Dump binary columns using hexadecimal notation (for example, 'abc' becomes 0x616263) | |||
--host | host | Host to connect to (IP address or hostname) | |||
--ignore-table=db_name.tbl_name | ignore-table | Do not dump the given table | |||
--include-master-host-port | include-master-host-port | Include MASTER_HOST/MASTER_PORT options in CHANGE MASTER statement produced with --dump-slave | 5.5.3 | ||
--insert-ignore | insert-ignore | Write INSERT IGNORE statements rather than INSERT statements | |||
--lines-terminated-by=string | lines-terminated-by | This option is used with the --tab option and has the same meaning as the corresponding clause for LOAD DATA INFILE | |||
--lock-all-tables | lock-all-tables | Lock all tables across all databases | |||
--lock-tables | lock-tables | Lock all tables before dumping them | |||
--log-error=file_name | log-error | Append warnings and errors to the named file | |||
--master-data[=value] | master-data | Write the binary log file name and position to the output | |||
--max_allowed_packet=value | max_allowed_packet | The maximum packet length to send to or receive from the server | |||
--net_buffer_length=value | net_buffer_length | The buffer size for TCP/IP and socket communication | |||
--no-autocommit | no-autocommit | Enclose the INSERT statements for each dumped table within SET autocommit = 0 and COMMIT statements | |||
--no-create-db | no-create-db | This option suppresses the CREATE DATABASE statements | |||
--no-create-info | no-create-info | Do not write CREATE TABLE statements that re-create each dumped table | |||
--no-data | no-data | Do not dump table contents | |||
--no-set-names | no-set-names | Same as --skip-set-charset | |||
--no-tablespaces | no-tablespaces | Do not write any CREATE LOGFILE GROUP or CREATE TABLESPACE statements in output | |||
--opt | opt | Shorthand for --add-drop-table --add-locks --create-options --disable-keys --extended-insert --lock-tables --quick --set-charset. | |||
--order-by-primary | order-by-primary | Dump each table's rows sorted by its primary key, or by its first unique index | |||
--password[=password] | password | The password to use when connecting to the server | |||
--pipe | On Windows, connect to server using a named pipe | ||||
--plugin-dir=path | plugin-dir=path | The directory where plugins are located | 5.5.9 | ||
--port=port_num | port | The TCP/IP port number to use for the connection | |||
--quick | quick | Retrieve rows for a table from the server a row at a time | |||
--quote-names | quote-names | Quote identifiers within backtick characters | |||
--replace | replace | Write REPLACE statements rather than INSERT statements | |||
--result-file=file | result-file | Direct output to a given file | |||
--routines | routines | Dump stored routines (procedures and functions) from the dumped databases | |||
--set-charset | set-charset | Add SET NAMES default_character_set to the output | |||
--single-transaction | single-transaction | This option issues a BEGIN SQL statement before dumping data from the server | |||
--skip-add-drop-table | skip-add-drop-table | Do not add a DROP TABLE statement before each CREATE TABLE statement | |||
--skip-add-locks | skip-add-locks | Do not add locks | |||
--skip-comments | skip-comments | Do not add comments to the dump file | |||
--skip-compact | skip-compact | Do not produce more compact output | |||
--skip-disable-keys | skip-disable-keys | Do not disable keys | |||
--skip-extended-insert | skip-extended-insert | Turn off extended-insert | |||
--skip-opt | skip-opt | Turn off the options set by --opt | |||
--skip-quick | skip-quick | Do not retrieve rows for a table from the server a row at a time | |||
--skip-quote-names | skip-quote-names | Do not quote identifiers | |||
--skip-set-charset | skip-set-charset | Suppress the SET NAMES statement | |||
--skip-triggers | skip-triggers | Do not dump triggers | |||
--skip-tz-utc | skip-tz-utc | Turn off tz-utc | |||
--ssl-ca=file_name | ssl-ca | The path to a file that contains a list of trusted SSL CAs | |||
--ssl-capath=dir_name | ssl-capath | The path to a directory that contains trusted SSL CA certificates in PEM format | |||
--ssl-cert=file_name | ssl-cert | The name of the SSL certificate file to use for establishing a secure connection | |||
--ssl-cipher=cipher_list | ssl-cipher | A list of allowable ciphers to use for SSL encryption | |||
--ssl-key=file_name | ssl-key | The name of the SSL key file to use for establishing a secure connection | |||
--ssl-verify-server-cert | ssl-verify-server-cert | The server's Common Name value in its certificate is verified against the host name used when connecting to the server | |||
--tab=path | tab | Produce tab-separated data files | |||
--tables | tables | Override the --databases or -B option | |||
--triggers | triggers | Dump triggers for each dumped table | |||
--tz-utc | tz-utc | Add SET TIME_ZONE='+00:00' to the dump file | |||
--user=user_name | user | The MySQL user name to use when connecting to the server | |||
--verbose | Verbose mode | ||||
--version | Display version information and exit | ||||
--where='where_condition' | where | Dump only rows selected by the given WHERE condition | |||
--xml | xml | Produce XML output |
--help
,-?
Display a help message and exit.
Add a
DROP DATABASE
statement before eachCREATE DATABASE
statement. This option is typically used in conjunction with the--all-databases
or--databases
option because noCREATE DATABASE
statements are written unless one of those options is specified.Add a
DROP TABLE
statement before eachCREATE TABLE
statement.Add a
DROP TRIGGER
statement before eachCREATE TRIGGER
statement.ЗамечаниеThis option is supported only by mysqldump as supplied with MySQL Cluster. It is not available when using MySQL Server 5.5.
Surround each table dump with
LOCK TABLES
andUNLOCK TABLES
statements. This results in faster inserts when the dump file is reloaded. See Section 7.2.2.1, “Speed ofINSERT
Statements”.--all-databases
,-A
Dump all tables in all databases. This is the same as using the
--databases
option and naming all the databases on the command line.Adds to a table dump all SQL statements needed to create any tablespaces used by an
NDBCLUSTER
table. This information is not otherwise included in the output from mysqldump. This option is currently relevant only to MySQL Cluster tables.Permit creation of column names that are keywords. This works by prefixing each column name with the table name.
For a slave dump produced with the
--dump-slave
option, add aSTOP SLAVE
statement before theCHANGE MASTER TO
statement and aSTART SLAVE
statement at the end of the output. This option was added in MySQL 5.5.3.On a computer having multiple network interfaces, this option can be used to select which interface is employed when connecting to the MySQL server.
This option is supported only in the version of mysqldump that is supplied with MySQL Cluster. It is not available in standard MySQL Server 5.5 releases.
The directory where character sets are installed. See Section 9.5, “Character Set Configuration”.
--comments
,-i
Write additional information in the dump file such as program version, server version, and host. This option is enabled by default. To suppress this additional information, use
--skip-comments
.Produce more compact output. This option enables the
--skip-add-drop-table
,--skip-add-locks
,--skip-comments
,--skip-disable-keys
, and--skip-set-charset
options.Produce output that is more compatible with other database systems or with older MySQL servers. The value of
name
can beansi
,mysql323
,mysql40
,postgresql
,oracle
,mssql
,db2
,maxdb
,no_key_options
,no_table_options
, orno_field_options
. To use several values, separate them by commas. These values have the same meaning as the corresponding options for setting the server SQL mode. See Section 5.1.6, “Server SQL Modes”.This option does not guarantee compatibility with other servers. It only enables those SQL mode values that are currently available for making dump output more compatible. For example,
--compatible=oracle
does not map data types to Oracle types or use Oracle comment syntax.This option requires a server version of 4.1.0 or higher. With older servers, it does nothing.
Use complete
INSERT
statements that include column names.--compress
,-C
Compress all information sent between the client and the server if both support compression.
Include all MySQL-specific table options in the
CREATE TABLE
statements.--databases
,-B
Dump several databases. Normally, mysqldump treats the first name argument on the command line as a database name and following names as table names. With this option, it treats all name arguments as database names.
CREATE DATABASE
andUSE
statements are included in the output before each new database.--debug[=
,debug_options
]-# [
debug_options
]Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default value isfile_name
''d:t:o,/tmp/mysqldump.trace'
.Print some debugging information when the program exits.
Print debugging information and memory and CPU usage statistics when the program exits.
The client-side authentication plugin to use. See Section 5.5.6, “Pluggable Authentication”.
This option was added in MySQL 5.5.9.
--default-character-set=
charset_name
Use
charset_name
as the default character set. See Section 9.5, “Character Set Configuration”. If no character set is specified, mysqldump usesutf8
, and earlier versions uselatin1
.Write
INSERT DELAYED
statements rather thanINSERT
statements.On a master replication server, delete the binary logs by sending a
PURGE BINARY LOGS
statement to the server after performing the dump operation. This option automatically enables--master-data
.--disable-keys
,-K
For each table, surround the
INSERT
statements with/*!40000 ALTER TABLE
andtbl_name
DISABLE KEYS */;/*!40000 ALTER TABLE
statements. This makes loading the dump file faster because the indexes are created after all rows are inserted. This option is effective only for nonunique indexes oftbl_name
ENABLE KEYS */;MyISAM
tables.If the
--comments
option is given, mysqldump produces a comment at the end of the dump of the following form:-- Dump completed on
DATE
However, the date causes dump files taken at different times to appear to be different, even if the data are otherwise identical.
--dump-date
and--skip-dump-date
control whether the date is added to the comment. The default is--dump-date
(include the date in the comment).--skip-dump-date
suppresses date printing.This option is similar to
--master-data
except that it is used to dump a replication slave server to produce a dump file that can be used to set up another server as a slave that has the same master as the dumped server. It causes the dump output to include aCHANGE MASTER TO
statement that indicates the binary log coordinates (file name and position) of the dumped slave's master (rather than the coordinates of the dumped server, as is done by the--master-data
option). These are the master server coordinates from which the slave should start replicating. This option was added in MySQL 5.5.3.The option value is handled the same way as for
--master-data
and has the same effect as--master-data
in terms of enabling or disabling other options and in how locking is handled.In conjunction with
--dump-slave
, the--apply-slave-statements
and--include-master-host-port
options can also be used.--events
,-E
Include Event Scheduler events for the dumped databases in the output.
Use multiple-row
INSERT
syntax that include severalVALUES
lists. This results in a smaller dump file and speeds up inserts when the file is reloaded.--fields-terminated-by=...
,--fields-enclosed-by=...
,--fields-optionally-enclosed-by=...
,--fields-escaped-by=...
These options are used with the
--tab
option and have the same meaning as the correspondingFIELDS
clauses forLOAD DATA INFILE
. See Section 12.2.6, “LOAD DATA INFILE
Синтаксис”.Deprecated. Use
--lock-all-tables
instead.--first-slave
was removed in MySQL 5.5.3.--flush-logs
,-F
Flush the MySQL server log files before starting the dump. This option requires the
RELOAD
privilege. If you use this option in combination with the--all-databases
option, the logs are flushed for each database dumped. The exception is when using--lock-all-tables
or--master-data
: In this case, the logs are flushed only once, corresponding to the moment that all tables are locked. If you want your dump and the log flush to happen at exactly the same moment, you should use--flush-logs
together with either--lock-all-tables
or--master-data
.Send a
FLUSH PRIVILEGES
statement to the server after dumping themysql
database. This option should be used any time the dump contains themysql
database and any other database that depends on the data in themysql
database for proper restoration.--force
,-f
Continue even if an SQL error occurs during a table dump.
One use for this option is to cause mysqldump to continue executing even when it encounters a view that has become invalid because the definition refers to a table that has been dropped. Without
--force
, mysqldump exits with an error message. With--force
, mysqldump prints the error message, but it also writes an SQL comment containing the view definition to the dump output and continues executing.--host=
,host_name
-h
host_name
Dump data from the MySQL server on the given host. The default host is
localhost
.Dump binary columns using hexadecimal notation (for example,
'abc'
becomes0x616263
). The affected data types areBINARY
,VARBINARY
, theBLOB
types, andBIT
.For the
CHANGE MASTER TO
statement in a slave dump produced with the--dump-slave
option, addMASTER_PORT
andMASTER_PORT
options for the host name and TCP/IP port number of the slave's master. This option was added in MySQL 5.5.3.--ignore-table=
db_name.tbl_name
Do not dump the given table, which must be specified using both the database and table names. To ignore multiple tables, use this option multiple times. This option also can be used to ignore views.
Write
INSERT IGNORE
statements rather thanINSERT
statements.This option is used with the
--tab
option and has the same meaning as the correspondingLINES
clause forLOAD DATA INFILE
. See Section 12.2.6, “LOAD DATA INFILE
Синтаксис”.Lock all tables across all databases. This is achieved by acquiring a global read lock for the duration of the whole dump. This option automatically turns off
--single-transaction
and--lock-tables
.--lock-tables
,-l
For each dumped database, lock all tables to be dumped before dumping them. The tables are locked with
READ LOCAL
to permit concurrent inserts in the case ofMyISAM
tables. For transactional tables such asInnoDB
,--single-transaction
is a much better option than--lock-tables
because it does not need to lock the tables at all.Because
--lock-tables
locks tables for each database separately, this option does not guarantee that the tables in the dump file are logically consistent between databases. Tables in different databases may be dumped in completely different states.Log warnings and errors by appending them to the named file. The default is to do no logging.
Use this option to dump a master replication server to produce a dump file that can be used to set up another server as a slave of the master. It causes the dump output to include a
CHANGE MASTER TO
statement that indicates the binary log coordinates (file name and position) of the dumped server. These are the master server coordinates from which the slave should start replicating after you load the dump file into the slave.If the option value is 2, the
CHANGE MASTER TO
statement is written as an SQL comment, and thus is informative only; it has no effect when the dump file is reloaded. If the option value is 1, the statement is not written as a comment and takes effect when the dump file is reloaded. If no option value is specified, the default value is 1.This option requires the
RELOAD
privilege and the binary log must be enabled.The
--master-data
option automatically turns off--lock-tables
. It also turns on--lock-all-tables
, unless--single-transaction
also is specified, in which case, a global read lock is acquired only for a short time at the beginning of the dump (see the description for--single-transaction
). In all cases, any action on logs happens at the exact moment of the dump.It is also possible to set up a slave by dumping an existing slave of the master. To do this, use the following procedure on the existing slave:
Stop the slave's SQL thread and get its current status:
mysql>
STOP SLAVE SQL_THREAD;
mysql>SHOW SLAVE STATUS;
From the output of the
SHOW SLAVE STATUS
statement, the binary log coordinates of the master server from which the new slave should start replicating are the values of theRelay_Master_Log_File
andExec_Master_Log_Pos
fields. Denote those values asfile_name
andfile_pos
.Dump the slave server:
shell>
mysqldump --master-data=2 --all-databases > dumpfile
Using
--master-data=2
works only if binary logging has been enabled on the slave. Otherwise, mysqldump fails with the error Binlogging on server not active. In this case you must handle any locking issues in another manner, using one or more of--add-locks
,--lock-tables
,--lock-all-tables
, or--single-transaction
, as required by your application and environment.Restart the slave:
mysql>
START SLAVE;
On the new slave, load the dump file:
shell>
mysql < dumpfile
On the new slave, set the replication coordinates to those of the master server obtained earlier:
mysql>
CHANGE MASTER TO
->MASTER_LOG_FILE = '
file_name
', MASTER_LOG_POS =file_pos
;The
CHANGE MASTER TO
statement might also need other parameters, such asMASTER_HOST
to point the slave to the correct master server host. Add any such parameters as necessary.
Enclose the
INSERT
statements for each dumped table withinSET autocommit = 0
andCOMMIT
statements.--no-create-db
,-n
This option suppresses the
CREATE DATABASE
statements that are otherwise included in the output if the--databases
or--all-databases
option is given.--no-create-info
,-t
Do not write
CREATE TABLE
statements that re-create each dumped table.ЗамечаниеThis option does not not exclude statements creating log file groups or tablespaces from mysqldump output; however, you can use the
--no-tablespaces
option for this purpose.--no-data
,-d
Do not write any table row information (that is, do not dump table contents). This is useful if you want to dump only the
CREATE TABLE
statement for the table (for example, to create an empty copy of the table by loading the dump file).--no-set-names
,-N
This has the same effect as
--skip-set-charset
.--no-tablespaces
,-y
This option suppresses all
CREATE LOGFILE GROUP
andCREATE TABLESPACE
statements in the output of mysqldump.This option is shorthand. It is the same as specifying
--add-drop-table
--add-locks
--create-options
--disable-keys
--extended-insert
--lock-tables
--quick
--set-charset
. It should give you a fast dump operation and produce a dump file that can be reloaded into a MySQL server quickly.The
--opt
option is enabled by default. Use--skip-opt
to disable it. See the discussion at the beginning of this section for information about selectively enabling or disabling a subset of the options affected by--opt
.Dump each table's rows sorted by its primary key, or by its first unique index, if such an index exists. This is useful when dumping a
MyISAM
table to be loaded into anInnoDB
table, but will make the dump operation take considerably longer.--password[=
,password
]-p[
password
]The password to use when connecting to the server. If you use the short option form (
-p
), you cannot have a space between the option and the password. If you omit thepassword
value following the--password
or-p
option on the command line, mysqldump prompts for one.Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
--pipe
,-W
On Windows, connect to the server using a named pipe. This option applies only if the server supports named-pipe connections.
The directory in which to look for plugins. It may be necessary to specify this option if the
--default-auth
option is used to specify an authentication plugin but mysqldump does not find it. See Section 5.5.6, “Pluggable Authentication”.This option was added in MySQL 5.5.9.
--port=
,port_num
-P
port_num
The TCP/IP port number to use for the connection.
--protocol={TCP|SOCKET|PIPE|MEMORY}
The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the permissible values, see Section 4.2.2, “Connecting to the MySQL Server”.
--quick
,-q
This option is useful for dumping large tables. It forces mysqldump to retrieve rows for a table from the server a row at a time rather than retrieving the entire row set and buffering it in memory before writing it out.
--quote-names
,-Q
Quote identifiers (such as database, table, and column names) within “
`
” characters. If theANSI_QUOTES
SQL mode is enabled, identifiers are quoted within “"
” characters. This option is enabled by default. It can be disabled with--skip-quote-names
, but this option should be given after any option such as--compatible
that may enable--quote-names
.--result-file=
,file_name
-r
file_name
Direct output to a given file. This option should be used on Windows to prevent newline “
\n
” characters from being converted to “\r\n
” carriage return/newline sequences. The result file is created and its previous contents overwritten, even if an error occurs while generating the dump.--routines
,-R
Included stored routines (procedures and functions) for the dumped databases in the output. Use of this option requires the
SELECT
privilege for themysql.proc
table. The output generated by using--routines
containsCREATE PROCEDURE
andCREATE FUNCTION
statements to re-create the routines. However, these statements do not include attributes such as the routine creation and modification timestamps. This means that when the routines are reloaded, they will be created with the timestamps equal to the reload time.If you require routines to be re-created with their original timestamp attributes, do not use
--routines
. Instead, dump and reload the contents of themysql.proc
table directly, using a MySQL account that has appropriate privileges for themysql
database.Prior to MySQL 5.5.21, this option had no effect when used together with the
--xml
option. (Bug #11760384, Bug #52792)Add
SET NAMES
to the output. This option is enabled by default. To suppress thedefault_character_set
SET NAMES
statement, use--skip-set-charset
.This option sends a
START TRANSACTION
SQL statement to the server before dumping data. It is useful only with transactional tables such asInnoDB
, because then it dumps the consistent state of the database at the time whenBEGIN
was issued without blocking any applications.When using this option, you should keep in mind that only
InnoDB
tables are dumped in a consistent state. For example, anyMyISAM
orMEMORY
tables dumped while using this option may still change state.While a
--single-transaction
dump is in process, to ensure a valid dump file (correct table contents and binary log coordinates), no other connection should use the following statements:ALTER TABLE
,CREATE TABLE
,DROP TABLE
,RENAME TABLE
,TRUNCATE TABLE
. A consistent read is not isolated from those statements, so use of them on a table to be dumped can cause theSELECT
that is performed by mysqldump to retrieve the table contents to obtain incorrect contents or fail.The
--single-transaction
option and the--lock-tables
option are mutually exclusive becauseLOCK TABLES
causes any pending transactions to be committed implicitly.This option is not supported for MySQL Cluster tables; the results cannot be guaranteed to be consistent due to the fact that the
NDBCLUSTER
storage engine supports only theREAD_COMMITTED
transaction isolation level. You should always useNDB
backup and restore instead.To dump large tables, you should combine the
--single-transaction
option with--quick
.See the description for the
--comments
option.See the description for the
--opt
option.--socket=
,path
-S
path
For connections to
localhost
, the Unix socket file to use, or, on Windows, the name of the named pipe to use.Options that begin with
--ssl
specify whether to connect to the server using SSL and indicate where to find SSL keys and certificates. See Section 5.5.8.3, “SSL Command Options”.--tab=
,path
-T
path
Produce tab-separated text-format data files. For each dumped table, mysqldump creates a
file that contains thetbl_name
.sqlCREATE TABLE
statement that creates the table, and the server writes a
file that contains its data. The option value is the directory in which to write the files.tbl_name
.txtЗамечаниеThis option should be used only when mysqldump is run on the same machine as the mysqld server. You must have the
FILE
privilege, and the server must have permission to write files in the directory that you specify.By default, the
.txt
data files are formatted using tab characters between column values and a newline at the end of each line. The format can be specified explicitly using the--fields-
andxxx
--lines-terminated-by
options.Column values are converted to the character set specified by the
--default-character-set
option.Override the
--databases
or-B
option. mysqldump regards all name arguments following the option as table names.Include triggers for each dumped table in the output. This option is enabled by default; disable it with
--skip-triggers
.This option enables
TIMESTAMP
columns to be dumped and reloaded between servers in different time zones. mysqldump sets its connection time zone to UTC and addsSET TIME_ZONE='+00:00'
to the dump file. Without this option,TIMESTAMP
columns are dumped and reloaded in the time zones local to the source and destination servers, which can cause the values to change if the servers are in different time zones.--tz-utc
also protects against changes due to daylight saving time.--tz-utc
is enabled by default. To disable it, use--skip-tz-utc
.--user=
,user_name
-u
user_name
The MySQL user name to use when connecting to the server.
--verbose
,-v
Verbose mode. Print more information about what the program does.
--version
,-V
Display version information and exit.
--where='
,where_condition
'-w '
where_condition
'Dump only rows selected by the given
WHERE
condition. Quotes around the condition are mandatory if it contains spaces or other characters that are special to your command interpreter.Examples:
--where="user='jimf'" -w"userid>1" -w"userid<1"
--xml
,-X
Write dump output as well-formed XML.
NULL
,'NULL'
, and Empty Values: For a column namedcolumn_name
, theNULL
value, an empty string, and the string value'NULL'
are distinguished from one another in the output generated by this option as follows.Value: XML Representation: NULL
(unknown value)<field name="
column_name
" xsi:nil="true" />''
(empty string)<field name="
column_name
"></field>'NULL'
(string value)<field name="
column_name
">NULL</field>The output from the mysql client when run using the
--xml
option also follows the preceding rules. (See Section 4.5.1.1, “mysql Options”.)XML output from mysqldump includes the XML namespace, as shown here:
shell>
mysqldump --xml -u root world City
<?xml version="1.0"?> <mysqldump xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <database name="world"> <table_structure name="City"> <field Field="ID" Type="int(11)" Null="NO" Key="PRI" Extra="auto_increment" /> <field Field="Name" Type="char(35)" Null="NO" Key="" Default="" Extra="" /> <field Field="CountryCode" Type="char(3)" Null="NO" Key="" Default="" Extra="" /> <field Field="District" Type="char(20)" Null="NO" Key="" Default="" Extra="" /> <field Field="Population" Type="int(11)" Null="NO" Key="" Default="0" Extra="" /> <key Table="City" Non_unique="0" Key_name="PRIMARY" Seq_in_index="1" Column_name="ID" Collation="A" Cardinality="4079" Null="" Index_type="BTREE" Comment="" /> <options Name="City" Engine="MyISAM" Version="10" Row_format="Fixed" Rows="4079" Avg_row_length="67" Data_length="273293" Max_data_length="18858823439613951" Index_length="43008" Data_free="0" Auto_increment="4080" Create_time="2007-03-31 01:47:01" Update_time="2007-03-31 01:47:02" Collation="latin1_swedish_ci" Create_options="" Comment="" /> </table_structure> <table_data name="City"> <row> <field name="ID">1</field> <field name="Name">Kabul</field> <field name="CountryCode">AFG</field> <field name="District">Kabol</field> <field name="Population">1780000</field> </row>...
<row> <field name="ID">4079</field> <field name="Name">Rafah</field> <field name="CountryCode">PSE</field> <field name="District">Rafah</field> <field name="Population">92020</field> </row> </table_data> </database> </mysqldump>
Prior to MySQL 5.5.21, this option prevented the
--routines
option from working
correctly—that is, no stored routines, triggers, or events
could be dumped in XML format. (Bug #11760384, Bug #52792)
You can also set the following variables by using
--
syntax:
var_name
=value
The maximum size of the buffer for client/server communication. The maximum is 1GB.
The initial size of the buffer for client/server communication. When creating multiple-row
INSERT
statements (as with the--extended-insert
or--opt
option), mysqldump creates rows up tonet_buffer_length
length. If you increase this variable, you should also ensure that thenet_buffer_length
variable in the MySQL server is at least this large.
A common use of mysqldump is for making a backup of an entire database:
shell> mysqldump db_name
> backup-file.sql
You can load the dump file back into the server like this:
shell> mysql db_name
< backup-file.sql
Or like this:
shell> mysql -e "source /path-to-backup/backup-file.sql
" db_name
mysqldump is also very useful for populating databases by copying data from one MySQL server to another:
shell> mysqldump --opt db_name
| mysql --host=remote_host
-C db_name
It is possible to dump several databases with one command:
shell> mysqldump --databases db_name1
[db_name2
...] > my_databases.sql
To dump all databases, use the
--all-databases
option:
shell> mysqldump --all-databases > all_databases.sql
For InnoDB
tables,
mysqldump provides a way of making an online
backup:
shell> mysqldump --all-databases --single-transaction > all_databases.sql
This backup acquires a global read lock on all tables (using
FLUSH TABLES WITH READ
LOCK
) at the beginning of the dump. As soon as this
lock has been acquired, the binary log coordinates are read and
the lock is released. If long updating statements are running
when the FLUSH
statement is
issued, the MySQL server may get stalled until those statements
finish. After that, the dump becomes lock free and does not
disturb reads and writes on the tables. If the update statements
that the MySQL server receives are short (in terms of execution
time), the initial lock period should not be noticeable, even
with many updates.
For point-in-time recovery (also known as “roll-forward,” when you need to restore an old backup and replay the changes that happened since that backup), it is often useful to rotate the binary log (see Section 5.2.4, “The Binary Log”) or at least know the binary log coordinates to which the dump corresponds:
shell> mysqldump --all-databases --master-data=2 > all_databases.sql
Or:
shell>mysqldump --all-databases --flush-logs --master-data=2
> all_databases.sql
The --master-data
and
--single-transaction
options
can be used simultaneously, which provides a convenient way to
make an online backup suitable for use prior to point-in-time
recovery if tables are stored using the
InnoDB
storage engine.
For more information on making backups, see Section 6.2, “Database Backup Methods”, and Section 6.3, “Пример Backup and Recovery Strategy”.
If you encounter problems backing up views, please read the section that covers restrictions on views which describes a workaround for backing up views when this fails due to insufficient privileges. See Section E.5, “Restrictions on Views”.
The mysqlimport client provides a
command-line interface to the
LOAD DATA
INFILE
SQL statement. Most options to
mysqlimport correspond directly to clauses of
LOAD DATA
INFILE
syntax. See Section 12.2.6, “LOAD DATA INFILE
Синтаксис”.
Invoke mysqlimport like this:
shell> mysqlimport [options
] db_name
textfile1
[textfile2
...]
For each text file named on the command line,
mysqlimport strips any extension from the
file name and uses the result to determine the name of the table
into which to import the file's contents. For example, files
named patient.txt
,
patient.text
, and
patient
all would be imported into a table
named patient
.
For additional information about mysqldump, see Section 6.4, “Using mysqldump for Backups”.
mysqlimport supports the following options,
which can be specified on the command line or in the
[mysqlimport]
and [client]
groups of an option file. mysqlimport also
supports the options for processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
Table 4.6. mysqlimport
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--columns=column_list | columns | This option takes a comma-separated list of column names as its value | |||
--compress | compress | Compress all information sent between the client and the server | |||
--debug[=debug_options] | debug | Write a debugging log | |||
--debug-check | debug-check | Print debugging information when the program exits | |||
--debug-info | debug-info | Print debugging information, memory and CPU statistics when the program exits | |||
--default-auth=plugin | default-auth=plugin | The authentication plugin to use | 5.5.10 | ||
--default-character-set=charset_name | default-character-set | Use charset_name as the default character set | |||
--delete | delete | Empty the table before importing the text file | |||
--fields-enclosed-by=string | fields-enclosed-by | This option has the same meaning as the corresponding clause for LOAD DATA INFILE | |||
--fields-escaped-by | fields-escaped-by | This option has the same meaning as the corresponding clause for LOAD DATA INFILE | |||
--fields-optionally-enclosed-by=string | fields-optionally-enclosed-by | This option has the same meaning as the corresponding clause for LOAD DATA INFILE | |||
--fields-terminated-by=string | fields-terminated-by | -- This option has the same meaning as the corresponding clause for LOAD DATA INFILE | |||
--force | force | Continue even if an SQL error occurs | |||
--help | Display help message and exit | ||||
--host=host_name | host | Connect to the MySQL server on the given host | |||
--ignore | ignore | See the description for the --replace option | |||
--ignore-lines=# | ignore-lines | Ignore the first N lines of the data file | |||
--lines-terminated-by=string | lines-terminated-by | This option has the same meaning as the corresponding clause for LOAD DATA INFILE | |||
--local | local | Read input files locally from the client host | |||
--lock-tables | lock-tables | Lock all tables for writing before processing any text files | |||
--low-priority | low-priority | Use LOW_PRIORITY when loading the table. | |||
--password[=password] | password | The password to use when connecting to the server | |||
--pipe | On Windows, connect to server using a named pipe | ||||
--plugin-dir=path | plugin-dir=path | The directory where plugins are located | 5.5.10 | ||
--port=port_num | port | The TCP/IP port number to use for the connection | |||
--protocol=type | protocol | The connection protocol to use | |||
--replace | replace | The --replace and --ignore options control handling of input rows that duplicate existing rows on unique key values | |||
--silent | silent | Produce output only when errors occur | |||
--socket=path | socket | For connections to localhost | |||
--ssl-ca=file_name | ssl-ca | The path to a file that contains a list of trusted SSL CAs | |||
--ssl-capath=dir_name | ssl-capath | The path to a directory that contains trusted SSL CA certificates in PEM format | |||
--ssl-cert=file_name | ssl-cert | The name of the SSL certificate file to use for establishing a secure connection | |||
--ssl-cipher=cipher_list | ssl-cipher | A list of allowable ciphers to use for SSL encryption | |||
--ssl-key=file_name | ssl-key | The name of the SSL key file to use for establishing a secure connection | |||
--ssl-verify-server-cert | ssl-verify-server-cert | The server's Common Name value in its certificate is verified against the host name used when connecting to the server | |||
--use-threads=# | use-threads | The number of threads for parallel file-loading | |||
--user=user_name, | user | The MySQL user name to use when connecting to the server | |||
--verbose | Verbose mode | ||||
--version | Display version information and exit |
--help
,-?
Display a help message and exit.
On a computer having multiple network interfaces, this option can be used to select which interface is employed when connecting to the MySQL server.
This option is supported only in the version of mysqlimport that is supplied with MySQL Cluster. It is not available in standard MySQL Server 5.5 releases.
The directory where character sets are installed. See Section 9.5, “Character Set Configuration”.
--columns=
,column_list
-c
column_list
This option takes a comma-separated list of column names as its value. The order of the column names indicates how to match data file columns with table columns.
--compress
,-C
Compress all information sent between the client and the server if both support compression.
--debug[=
,debug_options
]-# [
debug_options
]Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default isfile_name
''d:t:o'
.Print some debugging information when the program exits.
Print debugging information and memory and CPU usage statistics when the program exits.
--default-character-set=
charset_name
Use
charset_name
as the default character set. See Section 9.5, “Character Set Configuration”.The client-side authentication plugin to use. See Section 5.5.6, “Pluggable Authentication”.
This option was added in MySQL 5.5.10.
--delete
,-D
Empty the table before importing the text file.
--fields-terminated-by=...
,--fields-enclosed-by=...
,--fields-optionally-enclosed-by=...
,--fields-escaped-by=...
These options have the same meaning as the corresponding clauses for
LOAD DATA INFILE
. See Section 12.2.6, “LOAD DATA INFILE
Синтаксис”.--force
,-f
Ignore errors. For example, if a table for a text file does not exist, continue processing any remaining files. Without
--force
, mysqlimport exits if a table does not exist.--host=
,host_name
-h
host_name
Import data to the MySQL server on the given host. The default host is
localhost
.--ignore
,-i
See the description for the
--replace
option.Ignore the first
N
lines of the data file.This option has the same meaning as the corresponding clause for
LOAD DATA INFILE
. For example, to import Windows files that have lines terminated with carriage return/linefeed pairs, use--lines-terminated-by="\r\n"
. (You might have to double the backslashes, depending on the escaping conventions of your command interpreter.) See Section 12.2.6, “LOAD DATA INFILE
Синтаксис”.--local
,-L
Read input files locally from the client host.
--lock-tables
,-l
Lock all tables for writing before processing any text files. This ensures that all tables are synchronized on the server.
Use
LOW_PRIORITY
when loading the table. This affects only storage engines that use only table-level locking (such asMyISAM
,MEMORY
, andMERGE
).--password[=
,password
]-p[
password
]The password to use when connecting to the server. If you use the short option form (
-p
), you cannot have a space between the option and the password. If you omit thepassword
value following the--password
or-p
option on the command line, mysqlimport prompts for one.Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
--pipe
,-W
On Windows, connect to the server using a named pipe. This option applies only if the server supports named-pipe connections.
The directory in which to look for plugins. It may be necessary to specify this option if the
--default-auth
option is used to specify an authentication plugin but mysqlimport does not find it. See Section 5.5.6, “Pluggable Authentication”.This option was added in MySQL 5.5.10.
--port=
,port_num
-P
port_num
The TCP/IP port number to use for the connection.
--protocol={TCP|SOCKET|PIPE|MEMORY}
The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the permissible values, see Section 4.2.2, “Connecting to the MySQL Server”.
--replace
,-r
The
--replace
and--ignore
options control handling of input rows that duplicate existing rows on unique key values. If you specify--replace
, new rows replace existing rows that have the same unique key value. If you specify--ignore
, input rows that duplicate an existing row on a unique key value are skipped. If you do not specify either option, an error occurs when a duplicate key value is found, and the rest of the text file is ignored.--silent
,-s
Silent mode. Produce output only when errors occur.
--socket=
,path
-S
path
For connections to
localhost
, the Unix socket file to use, or, on Windows, the name of the named pipe to use.Options that begin with
--ssl
specify whether to connect to the server using SSL and indicate where to find SSL keys and certificates. See Section 5.5.8.3, “SSL Command Options”.--user=
,user_name
-u
user_name
The MySQL user name to use when connecting to the server.
Load files in parallel using
N
threads.--verbose
,-v
Verbose mode. Print more information about what the program does.
--version
,-V
Display version information and exit.
Here is a sample session that demonstrates use of mysqlimport:
shell>mysql -e 'CREATE TABLE imptest(id INT, n VARCHAR(30))' test
shell>ed
a 100 Max Sydow 101 Count Dracula . w imptest.txt 32 q shell>od -c imptest.txt
0000000 1 0 0 \t M a x S y d o w \n 1 0 0000020 1 \t C o u n t D r a c u l a \n 0000040 shell>mysqlimport --local test imptest.txt
test.imptest: Records: 2 Deleted: 0 Skipped: 0 Warnings: 0 shell>mysql -e 'SELECT * FROM imptest' test
+------+---------------+ | id | n | +------+---------------+ | 100 | Max Sydow | | 101 | Count Dracula | +------+---------------+
The mysqlshow client can be used to quickly see which databases exist, their tables, or a table's columns or indexes.
mysqlshow provides a command-line interface
to several SQL SHOW
statements.
See Section 12.7.5, “SHOW
Синтаксис”. The same information can be obtained
by using those statements directly. For example, you can issue
them from the mysql client program.
Invoke mysqlshow like this:
shell> mysqlshow [options
] [db_name
[tbl_name
[col_name
]]]
If no database is given, a list of database names is shown.
If no table is given, all matching tables in the database are shown.
If no column is given, all matching columns and column types in the table are shown.
The output displays only the names of those databases, tables, or columns for which you have some privileges.
If the last argument contains shell or SQL wildcard characters
(“*
”,
“?
”,
“%
”, or
“_
”), only those names that are
matched by the wildcard are shown. If a database name contains
any underscores, those should be escaped with a backslash (some
Unix shells require two) to get a list of the proper tables or
columns. “*
” and
“?
” characters are converted
into SQL “%
” and
“_
” wildcard characters. This
might cause some confusion when you try to display the columns
for a table with a “_
” in the
name, because in this case, mysqlshow shows
you only the table names that match the pattern. This is easily
fixed by adding an extra “%
”
last on the command line as a separate argument.
mysqlshow supports the following options,
which can be specified on the command line or in the
[mysqlshow]
and [client]
groups of an option file. mysqlshow also
supports the options for processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
Table 4.7. mysqlshow
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--bind-address=ip_address | bind-address | Use the specified network interface to connect to the MySQL Server | 5.5.8 | ||
--compress | compress | Compress all information sent between the client and the server | |||
--count | count | Show the number of rows per table | |||
--debug[=debug_options] | debug | Write a debugging log | |||
--debug-check | debug-check | Print debugging information when the program exits | |||
--debug-info | debug-info | Print debugging information, memory and CPU statistics when the program exits | |||
--default-auth=plugin | default-auth=plugin | The authentication plugin to use | 5.5.10 | ||
--default-character-set=charset_name | default-character-set | Use charset_name as the default character set | |||
--help | Display help message and exit | ||||
--host=host_name | host | Connect to the MySQL server on the given host | |||
--keys | keys | Show table indexes | |||
--password[=password] | password | The password to use when connecting to the server | |||
--pipe | On Windows, connect to server using a named pipe | ||||
--plugin-dir=path | plugin-dir=path | The directory where plugins are located | 5.5.10 | ||
--port=port_num | port | The TCP/IP port number to use for the connection | |||
--protocol=type | protocol | The connection protocol to use | |||
--show-table-type | Show a column indicating the table type | ||||
--socket=path | socket | For connections to localhost | |||
--ssl-ca=file_name | ssl-ca | The path to a file that contains a list of trusted SSL CAs | |||
--ssl-capath=dir_name | ssl-capath | The path to a directory that contains trusted SSL CA certificates in PEM format | |||
--ssl-cert=file_name | ssl-cert | The name of the SSL certificate file to use for establishing a secure connection | |||
--ssl-cipher=cipher_list | ssl-cipher | A list of allowable ciphers to use for SSL encryption | |||
--ssl-key=file_name | ssl-key | The name of the SSL key file to use for establishing a secure connection | |||
--ssl-verify-server-cert | ssl-verify-server-cert | The server's Common Name value in its certificate is verified against the host name used when connecting to the server | |||
--status | status | Display extra information about each table | |||
--user=user_name, | user | The MySQL user name to use when connecting to the server | |||
--verbose | Verbose mode | ||||
--version | Display version information and exit |
--help
,-?
Display a help message and exit.
On a computer having multiple network interfaces, this option can be used to select which interface is employed when connecting to the MySQL server.
This option is supported only in the version of mysqlshow that is supplied with MySQL Cluster. It is not available in standard MySQL Server 5.5 releases.
The directory where character sets are installed. See Section 9.5, “Character Set Configuration”.
--compress
,-C
Compress all information sent between the client and the server if both support compression.
Show the number of rows per table. This can be slow for non-
MyISAM
tables.--debug[=
,debug_options
]-# [
debug_options
]Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default isfile_name
''d:t:o'
.Print some debugging information when the program exits.
Print debugging information and memory and CPU usage statistics when the program exits.
--default-character-set=
charset_name
Use
charset_name
as the default character set. See Section 9.5, “Character Set Configuration”.The client-side authentication plugin to use. See Section 5.5.6, “Pluggable Authentication”.
This option was added in MySQL 5.5.10.
--host=
,host_name
-h
host_name
Connect to the MySQL server on the given host.
--keys
,-k
Show table indexes.
--password[=
,password
]-p[
password
]The password to use when connecting to the server. If you use the short option form (
-p
), you cannot have a space between the option and the password. If you omit thepassword
value following the--password
or-p
option on the command line, mysqlshow prompts for one.Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
--pipe
,-W
On Windows, connect to the server using a named pipe. This option applies only if the server supports named-pipe connections.
The directory in which to look for plugins. It may be necessary to specify this option if the
--default-auth
option is used to specify an authentication plugin but mysqlshow does not find it. See Section 5.5.6, “Pluggable Authentication”.This option was added in MySQL 5.5.10.
--port=
,port_num
-P
port_num
The TCP/IP port number to use for the connection.
--protocol={TCP|SOCKET|PIPE|MEMORY}
The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the permissible values, see Section 4.2.2, “Connecting to the MySQL Server”.
Show a column indicating the table type, as in
SHOW FULL TABLES
. The type isBASE TABLE
orVIEW
.--socket=
,path
-S
path
For connections to
localhost
, the Unix socket file to use, or, on Windows, the name of the named pipe to use.Options that begin with
--ssl
specify whether to connect to the server using SSL and indicate where to find SSL keys and certificates. See Section 5.5.8.3, “SSL Command Options”.--status
,-i
Display extra information about each table.
--user=
,user_name
-u
user_name
The MySQL user name to use when connecting to the server.
--verbose
,-v
Verbose mode. Print more information about what the program does. This option can be used multiple times to increase the amount of information.
--version
,-V
Display version information and exit.
mysqlslap is a diagnostic program designed to emulate client load for a MySQL server and to report the timing of each stage. It works as if multiple clients are accessing the server.
Invoke mysqlslap like this:
shell> mysqlslap [options
]
Some options such as --create
or --query
enable you to
specify a string containing an SQL statement or a file
containing statements. If you specify a file, by default it must
contain one statement per line. (That is, the implicit statement
delimiter is the newline character.) Use the
--delimiter
option to specify
a different delimiter, which enables you to specify statements
that span multiple lines or place multiple statements on a
single line. You cannot include comments in a file;
mysqlslap does not understand them.
mysqlslap runs in three stages:
Create schema, table, and optionally any stored programs or data you want to using for the test. This stage uses a single client connection.
Run the load test. This stage can use many client connections.
Clean up (disconnect, drop table if specified). This stage uses a single client connection.
Examples:
Supply your own create and query SQL statements, with 50 clients querying and 200 selects for each:
mysqlslap --delimiter=";" \ --create="CREATE TABLE a (b int);INSERT INTO a VALUES (23)" \ --query="SELECT * FROM a" --concurrency=50 --iterations=200
Let mysqlslap build the query SQL statement
with a table of two INT
columns
and three VARCHAR
columns. Use
five clients querying 20 times each. Do not create the table or
insert the data (that is, use the previous test's schema and
data):
mysqlslap --concurrency=5 --iterations=20 \ --number-int-cols=2 --number-char-cols=3 \ --auto-generate-sql
Tell the program to load the create, insert, and query SQL
statements from the specified files, where the
create.sql
file has multiple table creation
statements delimited by ';'
and multiple
insert statements delimited by ';'
. The
--query
file will have multiple queries
delimited by ';'
. Run all the load
statements, then run all the queries in the query file with five
clients (five times each):
mysqlslap --concurrency=5 \ --iterations=5 --query=query.sql --create=create.sql \ --delimiter=";"
mysqlslap supports the following options,
which can be specified on the command line or in the
[mysqlslap]
and [client]
groups of an option file. mysqlslap also
supports the options for processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
Table 4.8. mysqlslap
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--auto-generate-sql | auto-generate-sql | Generate SQL statements automatically when they are not supplied in files or using command options | |||
--auto-generate-sql-add-autoincrement | auto-generate-sql-add-autoincrement | Add AUTO_INCREMENT column to automatically generated tables | |||
--auto-generate-sql-execute-number=# | auto-generate-sql-execute-number | Specify how many queries to generate automatically | |||
--auto-generate-sql-guid-primary | auto-generate-sql-guid-primary | Add a GUID-based primary key to automatically generated tables | |||
--auto-generate-sql-load-type=type | auto-generate-sql-load-type | Specify how many queries to generate automatically | |||
--auto-generate-sql-secondary-indexes=# | auto-generate-sql-secondary-indexes | Specify how many secondary indexes to add to automatically generated tables | |||
--auto-generate-sql-unique-query-number=# | auto-generate-sql-unique-query-number | How many different queries to generate for automatic tests. | |||
--auto-generate-sql-unique-write-number=# | auto-generate-sql-unique-write-number | How many different queries to generate for --auto-generate-sql-write-number | |||
--auto-generate-sql-write-number=# | auto-generate-sql-write-number | How many row inserts to perform on each thread | |||
--commit=# | commit | How many statements to execute before committing. | |||
--compress | compress | Compress all information sent between the client and the server | |||
--concurrency=# | concurrency | The number of clients to simulate when issuing the SELECT statement | |||
--create=value | create | The file or string containing the statement to use for creating the table | |||
--create-and-drop-schema=value | create-and-drop-schema | The schema in which to run the tests; dropped at the end of the test run | 5.5.12 | ||
--create-schema=value | create-schema | The schema in which to run the tests | |||
--csv=[file] | csv | Generate output in comma-separated values format | |||
--debug[=debug_options] | debug | Write a debugging log | |||
--debug-check | debug-check | Print debugging information when the program exits | |||
--debug-info | debug-info | Print debugging information, memory and CPU statistics when the program exits | |||
--default-auth=plugin | default-auth=plugin | The authentication plugin to use | 5.5.10 | ||
--delimiter=str | delimiter | The delimiter to use in SQL statements | |||
--detach=# | detach | Detach (close and reopen) each connection after each N statements | |||
--engine=engine_name | engine | The storage engine to use for creating the table | |||
--help | Display help message and exit | ||||
--host=host_name | host | Connect to the MySQL server on the given host | |||
--iterations=# | iterations | The number of times to run the tests | |||
--number-char-cols=# | number-char-cols | The number of VARCHAR columns to use if --auto-generate-sql is specified | |||
--number-int-cols=# | number-int-cols | The number of INT columns to use if --auto-generate-sql is specified | |||
--number-of-queries=# | number-of-queries | Limit each client to approximately this number of queries | |||
--only-print | only-print | Do not connect to databases. mysqlslap only prints what it would have done | |||
--password[=password] | password | The password to use when connecting to the server | |||
--pipe | On Windows, connect to server using a named pipe | ||||
--plugin-dir=path | plugin-dir=path | The directory where plugins are located | 5.5.10 | ||
--port=port_num | port | The TCP/IP port number to use for the connection | |||
--post-query=value | post-query | The file or string containing the statement to execute after the tests have completed | |||
--post-system=str | post-system | The string to execute using system() after the tests have completed | |||
--pre-query=value | pre-query | The file or string containing the statement to execute before running the tests | |||
--pre-system=str | pre-system | The string to execute using system() before running the tests | |||
--protocol=type | protocol | The connection protocol to use | |||
--query=value | query | The file or string containing the SELECT statement to use for retrieving data | |||
--silent | silent | Silent mode | |||
--socket=path | socket | For connections to localhost | |||
--ssl-ca=file_name | ssl-ca | The path to a file that contains a list of trusted SSL CAs | |||
--ssl-capath=dir_name | ssl-capath | The path to a directory that contains trusted SSL CA certificates in PEM format | |||
--ssl-cert=file_name | ssl-cert | The name of the SSL certificate file to use for establishing a secure connection | |||
--ssl-cipher=cipher_list | ssl-cipher | A list of allowable ciphers to use for SSL encryption | |||
--ssl-key=file_name | ssl-key | The name of the SSL key file to use for establishing a secure connection | |||
--ssl-verify-server-cert | ssl-verify-server-cert | The server's Common Name value in its certificate is verified against the host name used when connecting to the server | |||
--user=user_name, | user | The MySQL user name to use when connecting to the server | |||
--verbose | Verbose mode | ||||
--version | Display version information and exit |
--help
,-?
Display a help message and exit.
Generate SQL statements automatically when they are not supplied in files or using command options.
--auto-generate-sql-add-autoincrement
Add an
AUTO_INCREMENT
column to automatically generated tables.--auto-generate-sql-execute-number=
N
Specify how many queries to generate automatically.
--auto-generate-sql-guid-primary
Add a GUID-based primary key to automatically generated tables.
--auto-generate-sql-load-type=
type
Specify the test load type. The permissible values are
read
(scan tables),write
(insert into tables),key
(read primary keys),update
(update primary keys), ormixed
(half inserts, half scanning selects). The default ismixed
.--auto-generate-sql-secondary-indexes=
N
Specify how many secondary indexes to add to automatically generated tables. By default, none are added.
--auto-generate-sql-unique-query-number=
N
How many different queries to generate for automatic tests. For example, if you run a
key
test that performs 1000 selects, you can use this option with a value of 1000 to run 1000 unique queries, or with a value of 50 to perform 50 different selects. The default is 10.--auto-generate-sql-unique-write-number=
N
How many different queries to generate for
--auto-generate-sql-write-number
. The default is 10.--auto-generate-sql-write-number=
N
How many row inserts to perform on each thread. The default is 100.
How many statements to execute before committing. The default is 0 (no commits are done).
--compress
,-C
Compress all information sent between the client and the server if both support compression.
--concurrency=
,N
-c
N
The number of clients to simulate when issuing the
SELECT
statement.The file or string containing the statement to use for creating the table.
--create-and-drop-schema=
value
The schema in which to run the tests. mysqlslap drops the schema at the end of the test run. This option was added in MySQL 5.5.12.
The schema in which to run the tests.
ЗамечаниеIf the
--auto-generate-sql
option is also given, mysqlslap drops the schema at the end of the test run. To avoid this, use the--create-and-drop-schema
option instead.Generate output in comma-separated values format. The output goes to the named file, or to the standard output if no file is given.
--debug[=
,debug_options
]-# [
debug_options
]Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default isfile_name
''d:t:o,/tmp/mysqlslap.trace'
.Print some debugging information when the program exits.
--debug-info
,-T
Print debugging information and memory and CPU usage statistics when the program exits.
The client-side authentication plugin to use. See Section 5.5.6, “Pluggable Authentication”.
This option was added in MySQL 5.5.10.
--delimiter=
,str
-F
str
The delimiter to use in SQL statements supplied in files or using command options.
Detach (close and reopen) each connection after each
N
statements. The default is 0 (connections are not detached).--engine=
,engine_name
-e
engine_name
The storage engine to use for creating tables.
--host=
,host_name
-h
host_name
Connect to the MySQL server on the given host.
--iterations=
,N
-i
N
The number of times to run the tests.
--number-char-cols=
,N
-x
N
The number of
VARCHAR
columns to use if--auto-generate-sql
is specified.--number-int-cols=
,N
-y
N
The number of
INT
columns to use if--auto-generate-sql
is specified.Limit each client to approximately this many queries. Query counting takes into account the statement delimiter. For example, if you invoke mysqlslap as follows, the
;
delimiter is recognized so that each instance of the query string counts as two queries. As a result, 5 rows (not 10) are inserted.shell>
mysqlslap --delimiter=";" --number-of-queries=10
--query="use test;insert into t values(null)"
Do not connect to databases. mysqlslap only prints what it would have done.
--password[=
,password
]-p[
password
]The password to use when connecting to the server. If you use the short option form (
-p
), you cannot have a space between the option and the password. If you omit thepassword
value following the--password
or-p
option on the command line, mysqlslap prompts for one.Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
--pipe
,-W
On Windows, connect to the server using a named pipe. This option applies only if the server supports named-pipe connections.
The directory in which to look for plugins. It may be necessary to specify this option if the
--default-auth
option is used to specify an authentication plugin but mysqlslap does not find it. See Section 5.5.6, “Pluggable Authentication”.This option was added in MySQL 5.5.10.
--port=
,port_num
-P
port_num
The TCP/IP port number to use for the connection.
The file or string containing the statement to execute after the tests have completed. This execution is not counted for timing purposes.
--shared-memory-base-name=
name
On Windows, the shared-memory name to use, for connections made using shared memory to a local server. This option applies only if the server supports shared-memory connections.
The string to execute using
system()
after the tests have completed. This execution is not counted for timing purposes.The file or string containing the statement to execute before running the tests. This execution is not counted for timing purposes.
The string to execute using
system()
before running the tests. This execution is not counted for timing purposes.--protocol={TCP|SOCKET|PIPE|MEMORY}
The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the permissible values, see Section 4.2.2, “Connecting to the MySQL Server”.
--query=
,value
-q
value
The file or string containing the
SELECT
statement to use for retrieving data.--silent
,-s
Silent mode. No output.
--socket=
,path
-S
path
For connections to
localhost
, the Unix socket file to use, or, on Windows, the name of the named pipe to use.Options that begin with
--ssl
specify whether to connect to the server using SSL and indicate where to find SSL keys and certificates. See Section 5.5.8.3, “SSL Command Options”.--user=
,user_name
-u
user_name
The MySQL user name to use when connecting to the server.
--verbose
,-v
Verbose mode. Print more information about what the program does. This option can be used multiple times to increase the amount of information.
--version
,-V
Display version information and exit.
- 4.6.1. innochecksum — Offline InnoDB File Checksum Utility
- 4.6.2. myisam_ftdump — Display Full-Text Index information
- 4.6.3. myisamchk — MyISAM Table-Maintenance Utility
- 4.6.4. myisamlog — Display MyISAM Log File Contents
- 4.6.5. myisampack — Generate Compressed, Read-Only MyISAM Tables
- 4.6.6. mysqlaccess — Client for Checking Access Privileges
- 4.6.7. mysqlbinlog — Utility for Processing Binary Log Files
- 4.6.8. mysqldumpslow — Summarize Slow Query Log Files
- 4.6.9. mysqlhotcopy — A Database Backup Program
- 4.6.10. mysql_convert_table_format — Convert Tables to Use a Given Storage Engine
- 4.6.11. mysql_find_rows — Extract SQL Statements from Files
- 4.6.12. mysql_fix_extensions — Normalize Table File Name Extensions
- 4.6.13. mysql_setpermission — Interactively Set Permissions in Grant Tables
- 4.6.14. mysql_waitpid — Kill Process and Wait for Its Termination
- 4.6.15. mysql_zap — Kill Processes That Match a Pattern
This section describes administrative programs and programs that perform miscellaneous utility operations.
innochecksum prints checksums for
InnoDB
files. This tool reads an
InnoDB
tablespace file, calculates the
checksum for each page, compares the calculated checksum to the
stored checksum, and reports mismatches, which indicate damaged
pages. It was originally developed to speed up verifying the
integrity of tablespace files after power outages but can also
be used after file copies. Because checksum mismatches will
cause InnoDB
to deliberately shut down a
running server, it can be preferable to use this tool rather
than waiting for a server in production usage to encounter the
damaged pages.
innochecksum cannot be used on tablespace
files that the server already has open. For such files, you
should use CHECK TABLE
to check
tables within the tablespace.
If checksum mismatches are found, you would normally restore the tablespace from backup or start the server and attempt to use mysqldump to make a backup of the tables within the tablespace.
Invoke innochecksum like this:
shell> innochecksum [options
] file_name
innochecksum supports the following options. For options that refer to page numbers, the numbers are zero-based.
myisam_ftdump displays information about
FULLTEXT
indexes in MyISAM
tables. It reads the MyISAM
index file
directly, so it must be run on the server host where the table
is located. Before using myisam_ftdump, be
sure to issue a FLUSH TABLES
statement first
if the server is running.
myisam_ftdump scans and dumps the entire index, which is not particularly fast. On the other hand, the distribution of words changes infrequently, so it need not be run often.
Invoke myisam_ftdump like this:
shell> myisam_ftdump [options
] tbl_name
index_num
The tbl_name
argument should be the
name of a MyISAM
table. You can also specify
a table by naming its index file (the file with the
.MYI
suffix). If you do not invoke
myisam_ftdump in the directory where the
table files are located, the table or index file name must be
preceded by the path name to the table's database directory.
Index numbers begin with 0.
Пример: Suppose that the test
database
contains a table named mytexttablel
that has
the following definition:
CREATE TABLE mytexttable ( id INT NOT NULL, txt TEXT NOT NULL, PRIMARY KEY (id), FULLTEXT (txt) ) ENGINE=MyISAM;
The index on id
is index 0 and the
FULLTEXT
index on txt
is
index 1. If your working directory is the
test
database directory, invoke
myisam_ftdump as follows:
shell> myisam_ftdump mytexttable 1
If the path name to the test
database
directory is /usr/local/mysql/data/test
,
you can also specify the table name argument using that path
name. This is useful if you do not invoke
myisam_ftdump in the database directory:
shell> myisam_ftdump /usr/local/mysql/data/test/mytexttable 1
You can use myisam_ftdump to generate a list of index entries in order of frequency of occurrence like this:
shell> myisam_ftdump -c mytexttable 1 | sort -r
myisam_ftdump supports the following options:
--help
,-h
-?
Display a help message and exit.
--count
,-c
Calculate per-word statistics (counts and global weights).
--dump
,-d
Dump the index, including data offsets and word weights.
--length
,-l
Report the length distribution.
--stats
,-s
Report global index statistics. This is the default operation if no other operation is specified.
--verbose
,-v
Verbose mode. Print more output about what the program does.
The myisamchk utility gets information about
your database tables or checks, repairs, or optimizes them.
myisamchk works with
MyISAM
tables (tables that have
.MYD
and .MYI
files
for storing data and indexes).
You can also use the CHECK TABLE
and REPAIR TABLE
statements to
check and repair MyISAM
tables. See
Section 12.7.2.2, “CHECK TABLE
Синтаксис”, and
Section 12.7.2.5, “REPAIR TABLE
Синтаксис”.
The use of myisamchk with partitioned tables is not supported.
It is best to make a backup of a table before performing a table repair operation; under some circumstances the operation might cause data loss. Possible causes include but are not limited to file system errors.
Invoke myisamchk like this:
shell> myisamchk [options
] tbl_name
...
The options
specify what you want
myisamchk to do. They are described in the
following sections. You can also get a list of options by
invoking myisamchk --help.
With no options, myisamchk simply checks your table as the default operation. To get more information or to tell myisamchk to take corrective action, specify options as described in the following discussion.
tbl_name
is the database table you
want to check or repair. If you run myisamchk
somewhere other than in the database directory, you must specify
the path to the database directory, because
myisamchk has no idea where the database is
located. In fact, myisamchk does not actually
care whether the files you are working on are located in a
database directory. You can copy the files that correspond to a
database table into some other location and perform recovery
operations on them there.
You can name several tables on the myisamchk
command line if you wish. You can also specify a table by naming
its index file (the file with the .MYI
suffix). This enables you to specify all tables in a directory
by using the pattern *.MYI
. For example, if
you are in a database directory, you can check all the
MyISAM
tables in that directory like this:
shell> myisamchk *.MYI
If you are not in the database directory, you can check all the tables there by specifying the path to the directory:
shell> myisamchk /path/to/database_dir/
*.MYI
You can even check all tables in all databases by specifying a wildcard with the path to the MySQL data directory:
shell> myisamchk /path/to/datadir/*/*
.MYI
The recommended way to quickly check all
MyISAM
tables is:
shell> myisamchk --silent --fast /path/to/datadir/*/*
.MYI
If you want to check all MyISAM
tables and
repair any that are corrupted, you can use the following
command:
shell>myisamchk --silent --force --fast --update-state \
--key_buffer_size=64M --sort_buffer_size=64M \
--read_buffer_size=1M --write_buffer_size=1M \
/path/to/datadir/*/*
.MYI
This command assumes that you have more than 64MB free. For more information about memory allocation with myisamchk, see Section 4.6.3.6, “myisamchk Memory Usage”.
For additional information about using
myisamchk, see
Section 6.6, “MyISAM
Table Maintenance and Crash Recovery”.
You must ensure that no other program is using the tables while you are running myisamchk. The most effective means of doing so is to shut down the MySQL server while running myisamchk, or to lock all tables that myisamchk is being used on.
Otherwise, when you run myisamchk, it may display the following error message:
warning: clients are using or haven't closed the table properly
This means that you are trying to check a table that has been
updated by another program (such as the
mysqld server) that hasn't yet closed the
file or that has died without closing the file properly, which
can sometimes lead to the corruption of one or more
MyISAM
tables.
If mysqld is running, you must force it to
flush any table modifications that are still buffered in
memory by using FLUSH
TABLES
. You should then ensure that no one is using
the tables while you are running myisamchk
However, the easiest way to avoid this problem is to use
CHECK TABLE
instead of
myisamchk to check tables. See
Section 12.7.2.2, “CHECK TABLE
Синтаксис”.
myisamchk supports the following options,
which can be specified on the command line or in the
[myisamchk]
group of an option file.
myisamchk also supports the options for
processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
Table 4.9. myisamchk
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--analyze | analyze | Analyze the distribution of key values | |||
--backup | backup | Make a backup of the .MYD file as file_name-time.BAK | |||
--block-search=offset | block-search | Find the record that a block at the given offset belongs to | |||
--check | check | Check the table for errors | |||
--check-only-changed | check-only-changed | Check only tables that have changed since the last check | |||
--correct-checksum | correct-checksum | Correct the checksum information for the table | |||
--data-file-length=len | data-file-length | Maximum length of the data file (when re-creating data file when it is full) | |||
--debug[=debug_options] | debug | Write a debugging log | |||
decode_bits=# | decode_bits | Decode_bits | |||
--description | description | Print some descriptive information about the table | |||
--extend-check | extend-check | Do very thorough table check or repair that tries to recover every possible row from the data file | |||
--fast | fast | Check only tables that haven't been closed properly | |||
--force | force | Do a repair operation automatically if myisamchk finds any errors in the table | |||
--force | force-recover | Overwrite old temporary files. For use with the -r or -o option | |||
ft_max_word_len=# | ft_max_word_len | Maximum word length for FULLTEXT indexes | |||
ft_min_word_len=# | ft_min_word_len | Minimum word length for FULLTEXT indexes | |||
ft_stopword_file=value | ft_stopword_file | Use stopwords from this file instead of built-in list | |||
--HELP | Display help message and exit | ||||
--help | Display help message and exit | ||||
--information | information | Print informational statistics about the table that is checked | |||
key_buffer_size=# | key_buffer_size | The size of the buffer used for index blocks for MyISAM tables | |||
--keys-used=val | keys-used | A bit-value that indicates which indexes to update | |||
--max-record-length=len | max-record-length | Skip rows larger than the given length if myisamchk cannot allocate memory to hold them | |||
--medium-check | medium-check | Do a check that is faster than an --extend-check operation | |||
myisam_block_size=# | myisam_block_size | Block size to be used for MyISAM index pages | |||
--parallel-recover | parallel-recover | Uses the same technique as -r and -n, but creates all the keys in parallel, using different threads (beta) | |||
--quick | quick | Achieve a faster repair by not modifying the data file. | |||
read_buffer_size=# | read_buffer_size | Each thread that does a sequential scan allocates a buffer of this size for each table it scans | |||
--read-only | read-only | Don't mark the table as checked | |||
--recover | recover | Do a repair that can fix almost any problem except unique keys that aren't unique | |||
--safe-recover | safe-recover | Do a repair using an old recovery method that reads through all rows in order and updates all index trees based on the rows found | |||
--set-auto-increment[=value] | set-auto-increment | Force AUTO_INCREMENT numbering for new records to start at the given value | |||
--set-collation=name | set-collation | Specify the collation to use for sorting table indexes | |||
--silent | silent | Silent mode | |||
sort_buffer_size=# | sort_buffer_size | The buffer that is allocated when sorting the index when doing a REPAIR or when creating indexes with CREATE INDEX or ALTER TABLE | |||
--sort-index | sort-index | Sort the index tree blocks in high-low order | |||
sort_key_blocks=# | sort_key_blocks | sort_key_blocks | |||
--sort-records=# | sort-records | Sort records according to a particular index | |||
--sort-recover | sort-recover | Force myisamchk to use sorting to resolve the keys even if the temporary files would be very large | |||
stats_method=value | stats_method | Specifies how MyISAM index statistics collection code should treat NULLs | |||
--tmpdir=path | tmpdir | Path of the directory to be used for storing temporary files | |||
--unpack | unpack | Unpack a table that was packed with myisampack | |||
--update-state | update-state | Store information in the .MYI file to indicate when the table was checked and whether the table crashed | |||
--verbose | Verbose mode | ||||
--version | Display version information and exit | ||||
write_buffer_size=# | write_buffer_size | Write buffer size |
The options described in this section can be used for any type of table maintenance operation performed by myisamchk. The sections following this one describe options that pertain only to specific operations, such as table checking or repairing.
--help
,-?
Display a help message and exit. Options are grouped by type of operation.
--HELP
,-H
Display a help message and exit. Options are presented in a single list.
--debug=
,debug_options
-#
debug_options
Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default isfile_name
''d:t:o,/tmp/myisamchk.trace'
.--silent
,-s
Silent mode. Write output only when errors occur. You can use
-s
twice (-ss
) to make myisamchk very silent.--verbose
,-v
Verbose mode. Print more information about what the program does. This can be used with
-d
and-e
. Use-v
multiple times (-vv
,-vvv
) for even more output.--version
,-V
Display version information and exit.
--wait
,-w
Instead of terminating with an error if the table is locked, wait until the table is unlocked before continuing. If you are running mysqld with external locking disabled, the table can be locked only by another myisamchk command.
You can also set the following variables by using
--
syntax:
var_name
=value
Variable | Default Value |
---|---|
decode_bits | 9 |
ft_max_word_len | version-dependent |
ft_min_word_len | 4 |
ft_stopword_file | built-in list |
key_buffer_size | 523264 |
myisam_block_size | 1024 |
read_buffer_size | 262136 |
sort_buffer_size | 2097144 |
sort_key_blocks | 16 |
stats_method | nulls_unequal |
write_buffer_size | 262136 |
The possible myisamchk variables and their default values can be examined with myisamchk --help:
sort_buffer_size
is used when the keys are
repaired by sorting keys, which is the normal case when you use
--recover
.
key_buffer_size
is used when you are checking
the table with --extend-check
or when the keys are repaired by inserting keys row by row into
the table (like when doing normal inserts). Repairing through
the key buffer is used in the following cases:
You use
--safe-recover
.The temporary files needed to sort the keys would be more than twice as big as when creating the key file directly. This is often the case when you have large key values for
CHAR
,VARCHAR
, orTEXT
columns, because the sort operation needs to store the complete key values as it proceeds. If you have lots of temporary space and you can force myisamchk to repair by sorting, you can use the--sort-recover
option.
Repairing through the key buffer takes much less disk space than using sorting, but is also much slower.
If you want a faster repair, set the
key_buffer_size
and
sort_buffer_size
variables to about 25% of
your available memory. You can set both variables to large
values, because only one of them is used at a time.
myisam_block_size
is the size used for index
blocks.
stats_method
influences how
NULL
values are treated for index statistics
collection when the --analyze
option is given. It acts like the
myisam_stats_method
system variable. For more
information, see the description of
myisam_stats_method
in
Section 5.1.3, “Server System Variables”, and
Section 7.3.7, “InnoDB
and MyISAM
Index Statistics
Collection”.
ft_min_word_len
and
ft_max_word_len
indicate the minimum and
maximum word length for FULLTEXT
indexes.
ft_stopword_file
names the stopword file.
These need to be set under the following circumstances.
If you use myisamchk to perform an operation
that modifies table indexes (such as repair or analyze), the
FULLTEXT
indexes are rebuilt using the
default full-text parameter values for minimum and maximum word
length and the stopword file unless you specify otherwise. This
can result in queries failing.
The problem occurs because these parameters are known only by
the server. They are not stored in MyISAM
index files. To avoid the problem if you have modified the
minimum or maximum word length or the stopword file in the
server, specify the same ft_min_word_len
,
ft_max_word_len
, and
ft_stopword_file
values to
myisamchk that you use for
mysqld. For example, if you have set the
minimum word length to 3, you can repair a table with
myisamchk like this:
shell> myisamchk --recover --ft_min_word_len=3 tbl_name
.MYI
To ensure that myisamchk and the server use
the same values for full-text parameters, you can place each one
in both the [mysqld]
and
[myisamchk]
sections of an option file:
[mysqld] ft_min_word_len=3 [myisamchk] ft_min_word_len=3
An alternative to using myisamchk is to use
the REPAIR TABLE
,
ANALYZE TABLE
,
OPTIMIZE TABLE
, or
ALTER TABLE
. These statements are
performed by the server, which knows the proper full-text
parameter values to use.
myisamchk supports the following options for table checking operations:
--check
,-c
Check the table for errors. This is the default operation if you specify no option that selects an operation type explicitly.
Check only tables that have changed since the last check.
--extend-check
,-e
Check the table very thoroughly. This is quite slow if the table has many indexes. This option should only be used in extreme cases. Normally, myisamchk or myisamchk --medium-check should be able to determine whether there are any errors in the table.
If you are using
--extend-check
and have plenty of memory, setting thekey_buffer_size
variable to a large value helps the repair operation run faster.See also the description of this option under table repair options.
For a description of the output format, see Section 4.6.3.5, “Obtaining Table Information with myisamchk”.
--fast
,-F
Check only tables that haven't been closed properly.
--force
,-f
Do a repair operation automatically if myisamchk finds any errors in the table. The repair type is the same as that specified with the
--recover
or-r
option.--information
,-i
Print informational statistics about the table that is checked.
--medium-check
,-m
Do a check that is faster than an
--extend-check
operation. This finds only 99.99% of all errors, which should be good enough in most cases.--read-only
,-T
Do not mark the table as checked. This is useful if you use myisamchk to check a table that is in use by some other application that does not use locking, such as mysqld when run with external locking disabled.
--update-state
,-U
Store information in the
.MYI
file to indicate when the table was checked and whether the table crashed. This should be used to get full benefit of the--check-only-changed
option, but you shouldn't use this option if the mysqld server is using the table and you are running it with external locking disabled.
myisamchk supports the following options for
table repair operations (operations performed when an option
such as --recover
or
--safe-recover
is given):
--backup
,-B
Make a backup of the
.MYD
file asfile_name
-time
.BAKThe directory where character sets are installed. See Section 9.5, “Character Set Configuration”.
Correct the checksum information for the table.
--data-file-length=
,len
-D
len
The maximum length of the data file (when re-creating data file when it is “full”).
--extend-check
,-e
Do a repair that tries to recover every possible row from the data file. Normally, this also finds a lot of garbage rows. Do not use this option unless you are desperate.
See also the description of this option under table checking options.
For a description of the output format, see Section 4.6.3.5, “Obtaining Table Information with myisamchk”.
--force
,-f
Overwrite old intermediate files (files with names like
) instead of aborting.tbl_name
.TMD--keys-used=
,val
-k
val
For myisamchk, the option value is a bit-value that indicates which indexes to update. Each binary bit of the option value corresponds to a table index, where the first index is bit 0. An option value of 0 disables updates to all indexes, which can be used to get faster inserts. Deactivated indexes can be reactivated by using myisamchk -r.
--no-symlinks
,-l
Do not follow symbolic links. Normally myisamchk repairs the table that a symlink points to. This option does not exist as of MySQL 4.0 because versions from 4.0 on do not remove symlinks during repair operations.
Skip rows larger than the given length if myisamchk cannot allocate memory to hold them.
Use the same technique as
-r
and-n
, but create all the keys in parallel, using different threads. This is beta-quality code. Use at your own risk!--quick
,-q
Achieve a faster repair by modifying only the index file, not the data file. You can specify this option twice to force myisamchk to modify the original data file in case of duplicate keys.
--recover
,-r
Do a repair that can fix almost any problem except unique keys that are not unique (which is an extremely unlikely error with
MyISAM
tables). If you want to recover a table, this is the option to try first. You should try--safe-recover
only if myisamchk reports that the table cannot be recovered using--recover
. (In the unlikely case that--recover
fails, the data file remains intact.)If you have lots of memory, you should increase the value of
sort_buffer_size
.--safe-recover
,-o
Do a repair using an old recovery method that reads through all rows in order and updates all index trees based on the rows found. This is an order of magnitude slower than
--recover
, but can handle a couple of very unlikely cases that--recover
cannot. This recovery method also uses much less disk space than--recover
. Normally, you should repair first using--recover
, and then with--safe-recover
only if--recover
fails.If you have lots of memory, you should increase the value of
key_buffer_size
.Change the character set used by the table indexes. This option was replaced by
--set-collation
in MySQL 5.0.3.Specify the collation to use for sorting table indexes. The character set name is implied by the first part of the collation name.
--sort-recover
,-n
Force myisamchk to use sorting to resolve the keys even if the temporary files would be very large.
--tmpdir=
,path
-t
path
The path of the directory to be used for storing temporary files. If this is not set, myisamchk uses the value of the
TMPDIR
environment variable.--tmpdir
can be set to a list of directory paths that are used successively in round-robin fashion for creating temporary files. The separator character between directory names is the colon (“:
”) on Unix and the semicolon (“;
”) on Windows.--unpack
,-u
Unpack a table that was packed with myisampack.
myisamchk supports the following options for actions other than table checks and repairs:
--analyze
,-a
Analyze the distribution of key values. This improves join performance by enabling the join optimizer to better choose the order in which to join the tables and which indexes it should use. To obtain information about the key distribution, use a myisamchk --description --verbose
tbl_name
command or theSHOW INDEX FROM
statement.tbl_name
--block-search=
,offset
-b
offset
Find the record that a block at the given offset belongs to.
--description
,-d
Print some descriptive information about the table. Specifying the
--verbose
option once or twice produces additional information. See Section 4.6.3.5, “Obtaining Table Information with myisamchk”.--set-auto-increment[=
,value
]-A[
value
]Force
AUTO_INCREMENT
numbering for new records to start at the given value (or higher, if there are existing records withAUTO_INCREMENT
values this large). Ifvalue
is not specified,AUTO_INCREMENT
numbers for new records begin with the largest value currently in the table, plus one.--sort-index
,-S
Sort the index tree blocks in high-low order. This optimizes seeks and makes table scans that use indexes faster.
--sort-records=
,N
-R
N
Sort records according to a particular index. This makes your data much more localized and may speed up range-based
SELECT
andORDER BY
operations that use this index. (The first time you use this option to sort a table, it may be very slow.) To determine a table's index numbers, useSHOW INDEX
, which displays a table's indexes in the same order that myisamchk sees them. Indexes are numbered beginning with 1.If keys are not packed (
PACK_KEYS=0
), they have the same length, so when myisamchk sorts and moves records, it just overwrites record offsets in the index. If keys are packed (PACK_KEYS=1
), myisamchk must unpack key blocks first, then re-create indexes and pack the key blocks again. (In this case, re-creating indexes is faster than updating offsets for each index.)
To obtain a description of a MyISAM
table or
statistics about it, use the commands shown here. The output
from these commands is explained later in this section.
Runs myisamchk in “describe mode” to produce a description of your table. If you start the MySQL server with external locking disabled, myisamchk may report an error for a table that is updated while it runs. However, because myisamchk does not change the table in describe mode, there is no risk of destroying data.
Adding
-v
runs myisamchk in verbose mode so that it produces more information about the table. Adding-v
a second time produces even more information.Shows only the most important information from a table. This operation is slow because it must read the entire table.
This is like
-eis
, but tells you what is being done.
The tbl_name
argument can be either
the name of a MyISAM
table or the name of its
index file, as described in Section 4.6.3, “myisamchk — MyISAM Table-Maintenance Utility”.
Multiple tbl_name
arguments can be
given.
Suppose that a table named person
has the
following structure. (The MAX_ROWS
table
option is included so that in the example output from
myisamchk shown later, some values are
smaller and fit the output format more easily.)
CREATE TABLE person ( id INT NOT NULL AUTO_INCREMENT, last_name VARCHAR(20) NOT NULL, first_name VARCHAR(20) NOT NULL, birth DATE, death DATE, PRIMARY KEY (id), INDEX (last_name, first_name), INDEX (birth) ) MAX_ROWS = 1000000;
Suppose also that the table has these data and index file sizes:
-rw-rw---- 1 mysql mysql 9347072 Aug 19 11:47 person.MYD -rw-rw---- 1 mysql mysql 6066176 Aug 19 11:47 person.MYI
Пример of myisamchk -dvv output:
MyISAM file: person Record format: Packed Character set: latin1_swedish_ci (8) File-version: 1 Creation time: 2009-08-19 16:47:41 Recover time: 2009-08-19 16:47:56 Status: checked,analyzed,optimized keys Auto increment key: 1 Last value: 306688 Data records: 306688 Deleted blocks: 0 Datafile parts: 306688 Deleted data: 0 Datafile pointer (bytes): 4 Keyfile pointer (bytes): 3 Datafile length: 9347072 Keyfile length: 6066176 Max datafile length: 4294967294 Max keyfile length: 17179868159 Recordlength: 54 table description: Key Start Len Index Type Rec/key Root Blocksize 1 2 4 unique long 1 99328 1024 2 6 20 multip. varchar prefix 512 3563520 1024 27 20 varchar 512 3 48 3 multip. uint24 NULL 306688 6065152 1024 Field Start Length Nullpos Nullbit Type 1 1 1 2 2 4 no zeros 3 6 21 varchar 4 27 21 varchar 5 48 3 1 1 no zeros 6 51 3 1 2 no zeros
Explanations for the types of information myisamchk produces are given here. “Keyfile” refers to the index file. “Record” and “row” are synonymous, as are “field” and “column.”
The initial part of the table description contains these values:
MyISAM file
Name of the
MyISAM
(index) file.Record format
The format used to store table rows. The preceding examples use
Fixed length
. Other possible values areCompressed
andPacked
. (Packed
corresponds to whatSHOW TABLE STATUS
reports asDynamic
.)Chararacter set
The table default character set.
File-version
Version of
MyISAM
format. Currently always 1.Creation time
When the data file was created.
Recover time
When the index/data file was last reconstructed.
Status
Table status flags. Possible values are
crashed
,open
,changed
,analyzed
,optimized keys
, andsorted index pages
.Auto increment key
,Last value
The key number associated the table's
AUTO_INCREMENT
column, and the most recently generated value for this column. These fields do not appear if there is no such column.Data records
The number of rows in the table.
Deleted blocks
How many deleted blocks still have reserved space. You can optimize your table to minimize this space. See Section 6.6.4, “
MyISAM
Table Optimization”.Datafile parts
For dynamic-row format, this indicates how many data blocks there are. For an optimized table without fragmented rows, this is the same as
Data records
.Deleted data
How many bytes of unreclaimed deleted data there are. You can optimize your table to minimize this space. See Section 6.6.4, “
MyISAM
Table Optimization”.Datafile pointer
The size of the data file pointer, in bytes. It is usually 2, 3, 4, or 5 bytes. Most tables manage with 2 bytes, but this cannot be controlled from MySQL yet. For fixed tables, this is a row address. For dynamic tables, this is a byte address.
Keyfile pointer
The size of the index file pointer, in bytes. It is usually 1, 2, or 3 bytes. Most tables manage with 2 bytes, but this is calculated automatically by MySQL. It is always a block address.
Max datafile length
How long the table data file can become, in bytes.
Max keyfile length
How long the table index file can become, in bytes.
Recordlength
How much space each row takes, in bytes.
The table description
part of the output
includes a list of all keys in the table. For each key,
myisamchk displays some low-level
information:
Key
This key's number. This value is shown only for the first column of the key. If this value is missing, the line corresponds to the second or later column of a multiple-column key. For the table shown in the example, there are two
table description
lines for the second index. This indicates that it is a multiple-part index with two parts.Start
Where in the row this portion of the index starts.
Len
How long this portion of the index is. For packed numbers, this should always be the full length of the column. For strings, it may be shorter than the full length of the indexed column, because you can index a prefix of a string column. The total length of a multiple-part key is the sum of the
Len
values for all key parts.Index
Whether a key value can exist multiple times in the index. Possible values are
unique
ormultip.
(multiple).Type
What data type this portion of the index has. This is a
MyISAM
data type with the possible valuespacked
,stripped
, orempty
.Root
Address of the root index block.
Blocksize
The size of each index block. By default this is 1024, but the value may be changed at compile time when MySQL is built from source.
Rec/key
This is a statistical value used by the optimizer. It tells how many rows there are per value for this index. A unique index always has a value of 1. This may be updated after a table is loaded (or greatly changed) with myisamchk -a. If this is not updated at all, a default value of 30 is given.
The last part of the output provides information about each column:
Field
The column number.
Start
The byte position of the column within table rows.
Length
The length of the column in bytes.
Nullpos
,Nullbit
For columns that can be
NULL
,MyISAM
storesNULL
values as a flag in a byte. Depending on how many nullable columns there are, there can be one or more bytes used for this purpose. TheNullpos
andNullbit
values, if nonempty, indicate which byte and bit contains that flag indicating whether the column isNULL
.The position and number of bytes used to store
NULL
flags is shown in the line for field 1. This is why there are sixField
lines for theperson
table even though it has only five columns.Type
The data type. The value may contain any of the following descriptors:
constant
All rows have the same value.
no endspace
Do not store endspace.
no endspace, not_always
Do not store endspace and do not do endspace compression for all values.
no endspace, no empty
Do not store endspace. Do not store empty values.
table-lookup
The column was converted to an
ENUM
.zerofill(
N
)The most significant
N
bytes in the value are always 0 and are not stored.no zeros
Do not store zeros.
always zero
Zero values are stored using one bit.
Huff tree
The number of the Huffman tree associated with the column.
Bits
The number of bits used in the Huffman tree.
The Huff tree
and Bits
fields are displayed if the table has been compressed with
myisampack. See Section 4.6.5, “myisampack — Generate Compressed, Read-Only MyISAM Tables”,
for an example of this information.
Пример of myisamchk -eiv output:
Checking MyISAM file: person
Data records: 306688 Deleted blocks: 0
- check file-size
- check record delete-chain
No recordlinks
- check key delete-chain
block_size 1024:
- check index reference
- check data record references index: 1
Key: 1: Keyblocks used: 98% Packed: 0% Max levels: 3
- check data record references index: 2
Key: 2: Keyblocks used: 99% Packed: 97% Max levels: 3
- check data record references index: 3
Key: 3: Keyblocks used: 98% Packed: -14% Max levels: 3
Total: Keyblocks used: 98% Packed: 89%
- check records and index references*** LOTS OF ROW NUMBERS DELETED ***
Records: 306688 M.recordlength: 25 Packed: 83%
Recordspace used: 97% Empty space: 2% Blocks/Record: 1.00
Record blocks: 306688 Delete blocks: 0
Record data: 7934464 Deleted data: 0
Lost space: 256512 Linkdata: 1156096
User time 43.08, System time 1.68
Maximum resident set size 0, Integral resident set size 0
Non-physical pagefaults 0, Physical pagefaults 0, Swaps 0
Blocks in 0 out 7, Messages in 0 out 0, Signals 0
Voluntary context switches 0, Involuntary context switches 0
Maximum memory usage: 1046926 bytes (1023k)
myisamchk -eiv output includes the following information:
Data records
The number of rows in the table.
Deleted blocks
How many deleted blocks still have reserved space. You can optimize your table to minimize this space. See Section 6.6.4, “
MyISAM
Table Optimization”.Key
The key number.
Keyblocks used
What percentage of the keyblocks are used. When a table has just been reorganized with myisamchk, the values are very high (very near theoretical maximum).
Packed
MySQL tries to pack key values that have a common suffix. This can only be used for indexes on
CHAR
andVARCHAR
columns. For long indexed strings that have similar leftmost parts, this can significantly reduce the space used. In the preceding example, the second key is 40 bytes long and a 97% reduction in space is achieved.Max levels
How deep the B-tree for this key is. Large tables with long key values get high values.
Records
How many rows are in the table.
M.recordlength
The average row length. This is the exact row length for tables with fixed-length rows, because all rows have the same length.
Packed
MySQL strips spaces from the end of strings. The
Packed
value indicates the percentage of savings achieved by doing this.Recordspace used
What percentage of the data file is used.
Empty space
What percentage of the data file is unused.
Blocks/Record
Average number of blocks per row (that is, how many links a fragmented row is composed of). This is always 1.0 for fixed-format tables. This value should stay as close to 1.0 as possible. If it gets too large, you can reorganize the table. See Section 6.6.4, “
MyISAM
Table Optimization”.Recordblocks
How many blocks (links) are used. For fixed-format tables, this is the same as the number of rows.
Deleteblocks
How many blocks (links) are deleted.
Recorddata
How many bytes in the data file are used.
Deleted data
How many bytes in the data file are deleted (unused).
Lost space
If a row is updated to a shorter length, some space is lost. This is the sum of all such losses, in bytes.
Linkdata
When the dynamic table format is used, row fragments are linked with pointers (4 to 7 bytes each).
Linkdata
is the sum of the amount of storage used by all such pointers.
Memory allocation is important when you run myisamchk. myisamchk uses no more memory than its memory-related variables are set to. If you are going to use myisamchk on very large tables, you should first decide how much memory you want it to use. The default is to use only about 3MB to perform repairs. By using larger values, you can get myisamchk to operate faster. For example, if you have more than 512MB RAM available, you could use options such as these (in addition to any other options you might specify):
shell>myisamchk --sort_buffer_size=256M \
--key_buffer_size=512M \
--read_buffer_size=64M \
--write_buffer_size=64M ...
Using --sort_buffer_size=16M
is probably enough
for most cases.
Be aware that myisamchk uses temporary files
in TMPDIR
. If TMPDIR
points to a memory file system, out of memory errors can easily
occur. If this happens, run myisamchk with
the
--tmpdir=
option to specify a directory located on a file system that has
more space.
path
When performing repair operations, myisamchk also needs a lot of disk space:
Twice the size of the data file (the original file and a copy). This space is not needed if you do a repair with
--quick
; in this case, only the index file is re-created. This space must be available on the same file system as the original data file, as the copy is created in the same directory as the original.Space for the new index file that replaces the old one. The old index file is truncated at the start of the repair operation, so you usually ignore this space. This space must be available on the same file system as the original data file.
When using
--recover
or--sort-recover
(but not when using--safe-recover
), you need space on disk for sorting. This space is allocated in the temporary directory (specified byTMPDIR
or--tmpdir=
). The following formula yields the amount of space required:path
(
largest_key
+row_pointer_length
) *number_of_rows
* 2You can check the length of the keys and the
row_pointer_length
with myisamchk -dvtbl_name
(see Section 4.6.3.5, “Obtaining Table Information with myisamchk”). Therow_pointer_length
andnumber_of_rows
values are theDatafile pointer
andData records
values in the table description. To determine thelargest_key
value, check theKey
lines in the table description. TheLen
column indicates the number of bytes for each key part. For a multiple-column index, the key size is the sum of theLen
values for all key parts.
If you have a problem with disk space during repair, you can try
--safe-recover
instead of
--recover
.
myisamlog processes the contents of a
MyISAM
log file.
Invoke myisamlog like this:
shell>myisamlog [
shell>options
] [log_file
[tbl_name
] ...]isamlog [
options
] [log_file
[tbl_name
] ...]
The default operation is update (-u
). If a
recovery is done (-r
), all writes and possibly
updates and deletes are done and errors are only counted. The
default log file name is myisam.log
for
myisamlog and isam.log
for isamlog if no
log_file
argument is given. If tables
are named on the command line, only those tables are updated.
myisamlog supports the following options:
Display a help message and exit.
Execute only
N
commands.Specify the maximum number of open files.
Display extra information before exiting.
Specify the starting offset.
Remove
N
components from path.Perform a recovery operation.
Specify record position file and record position.
Perform an update operation.
Verbose mode. Print more output about what the program does. This option can be given multiple times to produce more and more output.
Specify the write file.
Display version information.
The myisampack utility compresses
MyISAM
tables. myisampack
works by compressing each column in the table separately.
Usually, myisampack packs the data file 40%
to 70%.
When the table is used later, the server reads into memory the information needed to decompress columns. This results in much better performance when accessing individual rows, because you only have to uncompress exactly one row.
MySQL uses mmap()
when possible to perform
memory mapping on compressed tables. If
mmap()
does not work, MySQL falls back to
normal read/write file operations.
Please note the following:
If the mysqld server was invoked with external locking disabled, it is not a good idea to invoke myisampack if the table might be updated by the server during the packing process. It is safest to compress tables with the server stopped.
After packing a table, it becomes read only. This is generally intended (such as when accessing packed tables on a CD).
Invoke myisampack like this:
shell> myisampack [options
] file_name
...
Each file name argument should be the name of an index
(.MYI
) file. If you are not in the database
directory, you should specify the path name to the file. It is
permissible to omit the .MYI
extension.
After you compress a table with myisampack, you should use myisamchk -rq to rebuild its indexes. Section 4.6.3, “myisamchk — MyISAM Table-Maintenance Utility”.
myisampack supports the following options. It also reads option files and supports the options for processing them described at Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
--help
,-?
Display a help message and exit.
--backup
,-b
Make a backup of each table's data file using the name
.tbl_name
.OLDThe directory where character sets are installed. See Section 9.5, “Character Set Configuration”.
--debug[=
,debug_options
]-# [
debug_options
]Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default isfile_name
''d:t:o'
.--force
,-f
Produce a packed table even if it becomes larger than the original or if the intermediate file from an earlier invocation of myisampack exists. (myisampack creates an intermediate file named
in the database directory while it compresses the table. If you kill myisampack, thetbl_name
.TMD.TMD
file might not be deleted.) Normally, myisampack exits with an error if it finds that
exists. Withtbl_name
.TMD--force
, myisampack packs the table anyway.--join=
,big_tbl_name
-j
big_tbl_name
Join all tables named on the command line into a single packed table
big_tbl_name
. All tables that are to be combined must have identical structure (same column names and types, same indexes, and so forth).big_tbl_name
must not exist prior to the join operation. All source tables named on the command line to be merged intobig_tbl_name
must exist. The source tables are read for the join operation but not modified. The join operation does not create a.frm
file forbig_tbl_name
, so after the join operation finishes, copy the.frm
file from one of the source tables and name it
.big_tbl_name
.frm--silent
,-s
Silent mode. Write output only when errors occur.
--test
,-t
Do not actually pack the table, just test packing it.
--tmpdir=
,path
-T
path
Use the named directory as the location where myisampack creates temporary files.
--verbose
,-v
Verbose mode. Write information about the progress of the packing operation and its result.
--version
,-V
Display version information and exit.
--wait
,-w
Wait and retry if the table is in use. If the mysqld server was invoked with external locking disabled, it is not a good idea to invoke myisampack if the table might be updated by the server during the packing process.
The following sequence of commands illustrates a typical table compression session:
shell>ls -l station.*
-rw-rw-r-- 1 monty my 994128 Apr 17 19:00 station.MYD -rw-rw-r-- 1 monty my 53248 Apr 17 19:00 station.MYI -rw-rw-r-- 1 monty my 5767 Apr 17 19:00 station.frm shell>myisamchk -dvv station
MyISAM file: station Isam-version: 2 Creation time: 1996-03-13 10:08:58 Recover time: 1997-02-02 3:06:43 Data records: 1192 Deleted blocks: 0 Datafile parts: 1192 Deleted data: 0 Datafile pointer (bytes): 2 Keyfile pointer (bytes): 2 Max datafile length: 54657023 Max keyfile length: 33554431 Recordlength: 834 Record format: Fixed length table description: Key Start Len Index Type Root Blocksize Rec/key 1 2 4 unique unsigned long 1024 1024 1 2 32 30 multip. text 10240 1024 1 Field Start Length Type 1 1 1 2 2 4 3 6 4 4 10 1 5 11 20 6 31 1 7 32 30 8 62 35 9 97 35 10 132 35 11 167 4 12 171 16 13 187 35 14 222 4 15 226 16 16 242 20 17 262 20 18 282 20 19 302 30 20 332 4 21 336 4 22 340 1 23 341 8 24 349 8 25 357 8 26 365 2 27 367 2 28 369 4 29 373 4 30 377 1 31 378 2 32 380 8 33 388 4 34 392 4 35 396 4 36 400 4 37 404 1 38 405 4 39 409 4 40 413 4 41 417 4 42 421 4 43 425 4 44 429 20 45 449 30 46 479 1 47 480 1 48 481 79 49 560 79 50 639 79 51 718 79 52 797 8 53 805 1 54 806 1 55 807 20 56 827 4 57 831 4 shell>myisampack station.MYI
Compressing station.MYI: (1192 records) - Calculating statistics normal: 20 empty-space: 16 empty-zero: 12 empty-fill: 11 pre-space: 0 end-space: 12 table-lookups: 5 zero: 7 Original trees: 57 After join: 17 - Compressing file 87.14% Remember to run myisamchk -rq on compressed tables shell>ls -l station.*
-rw-rw-r-- 1 monty my 127874 Apr 17 19:00 station.MYD -rw-rw-r-- 1 monty my 55296 Apr 17 19:04 station.MYI -rw-rw-r-- 1 monty my 5767 Apr 17 19:00 station.frm shell>myisamchk -dvv station
MyISAM file: station Isam-version: 2 Creation time: 1996-03-13 10:08:58 Recover time: 1997-04-17 19:04:26 Data records: 1192 Deleted blocks: 0 Datafile parts: 1192 Deleted data: 0 Datafile pointer (bytes): 3 Keyfile pointer (bytes): 1 Max datafile length: 16777215 Max keyfile length: 131071 Recordlength: 834 Record format: Compressed table description: Key Start Len Index Type Root Blocksize Rec/key 1 2 4 unique unsigned long 10240 1024 1 2 32 30 multip. text 54272 1024 1 Field Start Length Type Huff tree Bits 1 1 1 constant 1 0 2 2 4 zerofill(1) 2 9 3 6 4 no zeros, zerofill(1) 2 9 4 10 1 3 9 5 11 20 table-lookup 4 0 6 31 1 3 9 7 32 30 no endspace, not_always 5 9 8 62 35 no endspace, not_always, no empty 6 9 9 97 35 no empty 7 9 10 132 35 no endspace, not_always, no empty 6 9 11 167 4 zerofill(1) 2 9 12 171 16 no endspace, not_always, no empty 5 9 13 187 35 no endspace, not_always, no empty 6 9 14 222 4 zerofill(1) 2 9 15 226 16 no endspace, not_always, no empty 5 9 16 242 20 no endspace, not_always 8 9 17 262 20 no endspace, no empty 8 9 18 282 20 no endspace, no empty 5 9 19 302 30 no endspace, no empty 6 9 20 332 4 always zero 2 9 21 336 4 always zero 2 9 22 340 1 3 9 23 341 8 table-lookup 9 0 24 349 8 table-lookup 10 0 25 357 8 always zero 2 9 26 365 2 2 9 27 367 2 no zeros, zerofill(1) 2 9 28 369 4 no zeros, zerofill(1) 2 9 29 373 4 table-lookup 11 0 30 377 1 3 9 31 378 2 no zeros, zerofill(1) 2 9 32 380 8 no zeros 2 9 33 388 4 always zero 2 9 34 392 4 table-lookup 12 0 35 396 4 no zeros, zerofill(1) 13 9 36 400 4 no zeros, zerofill(1) 2 9 37 404 1 2 9 38 405 4 no zeros 2 9 39 409 4 always zero 2 9 40 413 4 no zeros 2 9 41 417 4 always zero 2 9 42 421 4 no zeros 2 9 43 425 4 always zero 2 9 44 429 20 no empty 3 9 45 449 30 no empty 3 9 46 479 1 14 4 47 480 1 14 4 48 481 79 no endspace, no empty 15 9 49 560 79 no empty 2 9 50 639 79 no empty 2 9 51 718 79 no endspace 16 9 52 797 8 no empty 2 9 53 805 1 17 1 54 806 1 3 9 55 807 20 no empty 3 9 56 827 4 no zeros, zerofill(2) 2 9 57 831 4 no zeros, zerofill(1) 2 9
myisampack displays the following kinds of information:
normal
The number of columns for which no extra packing is used.
empty-space
The number of columns containing values that are only spaces. These occupy one bit.
empty-zero
The number of columns containing values that are only binary zeros. These occupy one bit.
empty-fill
The number of integer columns that do not occupy the full byte range of their type. These are changed to a smaller type. For example, a
BIGINT
column (eight bytes) can be stored as aTINYINT
column (one byte) if all its values are in the range from-128
to127
.pre-space
The number of decimal columns that are stored with leading spaces. In this case, each value contains a count for the number of leading spaces.
end-space
The number of columns that have a lot of trailing spaces. In this case, each value contains a count for the number of trailing spaces.
table-lookup
The column had only a small number of different values, which were converted to an
ENUM
before Huffman compression.zero
The number of columns for which all values are zero.
Original trees
The initial number of Huffman trees.
After join
The number of distinct Huffman trees left after joining trees to save some header space.
After a table has been compressed, the Field
lines displayed by myisamchk -dvv include
additional information about each column:
Type
The data type. The value may contain any of the following descriptors:
constant
All rows have the same value.
no endspace
Do not store endspace.
no endspace, not_always
Do not store endspace and do not do endspace compression for all values.
no endspace, no empty
Do not store endspace. Do not store empty values.
table-lookup
The column was converted to an
ENUM
.zerofill(
N
)The most significant
N
bytes in the value are always 0 and are not stored.no zeros
Do not store zeros.
always zero
Zero values are stored using one bit.
Huff tree
The number of the Huffman tree associated with the column.
Bits
The number of bits used in the Huffman tree.
After you run myisampack, you must run myisamchk to re-create any indexes. At this time, you can also sort the index blocks and create statistics needed for the MySQL optimizer to work more efficiently:
shell> myisamchk -rq --sort-index --analyze tbl_name
.MYI
After you have installed the packed table into the MySQL database directory, you should execute mysqladmin flush-tables to force mysqld to start using the new table.
To unpack a packed table, use the
--unpack
option to
myisamchk.
mysqlaccess is a diagnostic tool that Yves
Carlier has provided for the MySQL distribution. It checks the
access privileges for a host name, user name, and database
combination. Note that mysqlaccess checks
access using only the user
,
db
, and host
tables. It
does not check table, column, or routine privileges specified in
the tables_priv
,
columns_priv
, or
procs_priv
tables.
Invoke mysqlaccess like this:
shell> mysqlaccess [host_name
[user_name
[db_name
]]] [options
]
mysqlaccess supports the following options.
Table 4.10. mysqlaccess
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--brief | brief | Generate reports in single-line tabular format | |||
--commit | commit | Copy the new access privileges from the temporary tables to the original grant tables | |||
--copy | copy | Reload the temporary grant tables from original ones | |||
--db=db_name | db | Specify the database name | |||
--debug=# | debug | Specify the debug level | |||
--help | Display help message and exit | ||||
--host=host_name | host | Connect to the MySQL server on the given host | |||
--howto | howto | Display some examples that show how to use mysqlaccess | |||
--old_server | old_server | Assume that the server is an old MySQL server (prior to MySQL 3.21) | |||
--password[=password] | password | The password to use when connecting to the server | |||
--plan | plan | Display suggestions and ideas for future releases | |||
--preview | preview | Show the privilege differences after making changes to the temporary grant tables | |||
--relnotes | relnotes | Display the release notes | |||
--rhost=host_name | rhost | Connect to the MySQL server on the given host | |||
--rollback | rollback | Undo the most recent changes to the temporary grant tables. | |||
--spassword[=password] | spassword | The password to use when connecting to the server as the superuser | |||
--superuser=user_name | superuser | Specify the user name for connecting as the superuser | |||
--table | table | Generate reports in table format | |||
--user=user_name, | user | The MySQL user name to use when connecting | |||
--version | Display version information and exit |
--help
,-?
Display a help message and exit.
--brief
,-b
Generate reports in single-line tabular format.
Copy the new access privileges from the temporary tables to the original grant tables. The grant tables must be flushed for the new privileges to take effect. (For example, execute a mysqladmin reload command.)
Reload the temporary grant tables from original ones.
--db=
,db_name
-d
db_name
Specify the database name.
Specify the debug level.
N
can be an integer from 0 to 3.--host=
,host_name
-h
host_name
The host name to use in the access privileges.
Display some examples that show how to use mysqlaccess.
Assume that the server is an old MySQL server (before MySQL 3.21) that does not yet know how to handle full
WHERE
clauses.--password[=
,password
]-p[
password
]The password to use when connecting to the server. If you omit the
password
value following the--password
or-p
option on the command line, mysqlaccess prompts for one.Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”.
Display suggestions and ideas for future releases.
Show the privilege differences after making changes to the temporary grant tables.
Display the release notes.
--rhost=
,host_name
-H
host_name
Connect to the MySQL server on the given host.
Undo the most recent changes to the temporary grant tables.
--spassword[=
,password
]-P[
password
]The password to use when connecting to the server as the superuser. If you omit the
password
value following the--spassword
or-p
option on the command line, mysqlaccess prompts for one.Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”.
--superuser=
,user_name
-U
user_name
Specify the user name for connecting as the superuser.
--table
,-t
Generate reports in table format.
--user=
,user_name
-u
user_name
The user name to use in the access privileges.
--version
,-v
Display version information and exit.
If your MySQL distribution is installed in some nonstandard
location, you must change the location where
mysqlaccess expects to find the
mysql client. Edit the
mysqlaccess
script at approximately line
18. Search for a line that looks like this:
$MYSQL = '/usr/local/bin/mysql'; # path to mysql executable
Change the path to reflect the location where
mysql actually is stored on your system. If
you do not do this, a Broken pipe
error will
occur when you run mysqlaccess.
The server's binary log consists of files containing “events” that describe modifications to database contents. The server writes these files in binary format. To display their contents in text format, use the mysqlbinlog utility. You can also use mysqlbinlog to display the contents of relay log files written by a slave server in a replication setup because relay logs have the same format as binary logs. The binary log and relay log are discussed further in Section 5.2.4, “The Binary Log”, and Section 15.2.2, “Replication Relay and Status Logs”.
Invoke mysqlbinlog like this:
shell> mysqlbinlog [options
] log_file
...
For example, to display the contents of the binary log file
named binlog.000003
, use this command:
shell> mysqlbinlog binlog.0000003
The output includes events contained in
binlog.000003
. For statement-based logging,
event information includes the SQL statement, the ID of the
server on which it was executed, the timestamp when the
statement was executed, how much time it took, and so forth. For
row-based logging, the event indicates a row change rather than
an SQL statement. See Section 15.1.2, “Replication Formats”, for
information about logging modes.
Events are preceded by header comments that provide additional information. For example:
# at 141 #100309 9:28:36 server id 123 end_log_pos 245 Query thread_id=3350 exec_time=11 error_code=0
In the first line, the number following at
indicates the starting position of the event in the binary log
file.
The second line starts with a date and time indicating when the
statement started on the server where the event originated. For
replication, this timestamp is propagated to slave servers.
server id
is the
server_id
value of the server
where the event originated. end_log_pos
indicates where the next event starts (that is, it is the end
position of the current event + 1). thread_id
indicates which thread executed the event.
exec_time
is the time spent executing the
event, on a master server. On a slave, it is the difference of
the end execution time on the slave minus the beginning
execution time on the master. The difference serves as an
indicator of how much replication lags behind the master.
error_code
indicates the result from
executing the event. Zero means that no error occurred.
The output from mysqlbinlog can be re-executed (for example, by using it as input to mysql) to redo the statements in the log. This is useful for recovery operations after a server crash. For other usage examples, see the discussion later in this section and in Section 6.5, “Point-in-Time (Incremental) Recovery Using the Binary Log”.
Normally, you use mysqlbinlog to read binary
log files directly and apply them to the local MySQL server. It
is also possible to read binary logs from a remote server by
using the
--read-from-remote-server
option. To read remote binary logs, the connection parameter
options can be given to indicate how to connect to the server.
These options are --host
,
--password
,
--port
,
--protocol
,
--socket
, and
--user
; they are ignored
except when you also use the
--read-from-remote-server
option.
mysqlbinlog supports the following options,
which can be specified on the command line or in the
[mysqlbinlog]
and [client]
groups of an option file. mysqlbinlog also
supports the options for processing option files described at
Section 4.2.3.3.1, “Command-Line Options that Affect Option-File Handling”.
Table 4.11. mysqlbinlog
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--base64-output[=value] | base64-output | Print binary log entries using base-64 encoding | |||
--character-sets-dir=path | character-sets-dir | The directory where character sets are installed | |||
--database=db_name | database | List entries for just this database | |||
--debug[=debug_options] | debug | Write a debugging log | |||
--debug-check | debug-check | Print debugging information when the program exits | |||
--debug-info | debug-info | Print debugging information, memory and CPU statistics when the program exits | |||
--default-auth=plugin | default-auth=plugin | The authentication plugin to use | 5.5.10 | ||
--disable-log-bin | disable-log-bin | Disable binary logging | |||
--force-read | force-read | If mysqlbinlog reads a binary log event that it does not recognize, it prints a warning | |||
--help | Display help message and exit | ||||
--hexdump | hexdump | Display a hex dump of the log in comments | |||
--host=host_name | host | Connect to the MySQL server on the given host | |||
--local-load=path | local-load | Prepare local temporary files for LOAD DATA INFILE in the specified directory | |||
--offset=# | offset | Skip the first N entries in the log | |||
--password[=password] | password | The password to use when connecting to the server | |||
--plugin-dir=path | plugin-dir=path | The directory where plugins are located | 5.5.10 | ||
--port=port_num | port | The TCP/IP port number to use for the connection | |||
--protocol=type | protocol | The connection protocol to use | |||
--read-from-remote-server | read-from-remote-server | Read the binary log from a MySQL server rather than reading a local log file | |||
--result-file=name | result-file | Direct output to the given file | |||
--server-id=id | server-id | Extract only those events created by the server having the given server ID | |||
--set-charset=charset_name | set-charset | Add a SET NAMES charset_name statement to the output | |||
--short-form | short-form | Display only the statements contained in the log | |||
--socket=path | socket | For connections to localhost | |||
--start-datetime=datetime | start-datetime | Start reading the binary log at the first event having a timestamp equal to or later than the datetime argument | |||
--start-position=# | start-position | Start reading the binary log at the first event having a position equal to or greater than the argument | |||
--stop-datetime=datetime | stop-datetime | Stop reading the binary log at the first event having a timestamp equal to or greater than the datetime argument | |||
--stop-position=# | stop-position | Stop reading the binary log at the first event having a position equal to or greater than the argument | |||
--to-last-log | to-last-log | Do not stop at the end of the requested binary log from a MySQL server, but rather continue printing until the end of the last binary log | |||
--user=user_name, | user | The MySQL user name to use when connecting to the server | |||
--verbose | Reconstruct row events as SQL statements | ||||
--version | Display version information and exit |
--help
,-?
Display a help message and exit.
This option determines when events should be displayed encoded as base-64 strings using
BINLOG
statements. The option has these permissible values (not case sensitive):AUTO
("automatic") orUNSPEC
("unspecified") displaysBINLOG
statements automatically when necessary (that is, for format description events and row events). If no--base64-output
option is given, the effect is the same as--base64-output=AUTO
.ЗамечаниеAutomatic
BINLOG
display is the only safe behavior if you intend to use the output of mysqlbinlog to re-execute binary log file contents. The other option values are intended only for debugging or testing purposes because they may produce output that does not include all events in executable form.ALWAYS
displaysBINLOG
statements whenever possible. If the--base64-output
option is given without a value, the effect is the same as--base64-output=ALWAYS
.ЗамечаниеChanges to replication in MySQL 5.6 make output generated by this option unusable, so
ALWAYS
is deprecated as of MySQL 5.5.8 and will be an invalid value in MySQL 5.6NEVER
causesBINLOG
statements not to be displayed. mysqlbinlog exits with an error if a row event is found that must be displayed usingBINLOG
.DECODE-ROWS
specifies to mysqlbinlog that you intend for row events to be decoded and displayed as commented SQL statements by also specifying the--verbose
option. LikeNEVER
,DECODE-ROWS
suppresses display ofBINLOG
statements, but unlikeNEVER
, it does not exit with an error if a row event is found.
For examples that show the effect of
--base64-output
and--verbose
on row event output, see Section 4.6.7.2, “mysqlbinlog Row Event Display”.On a computer having multiple network interfaces, this option can be used to select which interface is employed when connecting to the MySQL server.
This option is supported beginning with MySQL 5.5.8.
The directory where character sets are installed. See Section 9.5, “Character Set Configuration”.
--database=
,db_name
-d
db_name
This option causes mysqlbinlog to output entries from the binary log (local log only) that occur while
db_name
is been selected as the default database byUSE
.The
--database
option for mysqlbinlog is similar to the--binlog-do-db
option for mysqld, but can be used to specify only one database. If--database
is given multiple times, only the last instance is used.The effects of this option depend on whether the statement-based or row-based logging format is in use, in the same way that the effects of
--binlog-do-db
depend on whether statement-based or row-based logging is in use.Statement-based logging. The
--database
option works as follows:While
db_name
is the default database, statements are output whether they modify tables indb_name
or a different database.Unless
db_name
is selected as the default database, statements are not output, even if they modify tables indb_name
.There is an exception for
CREATE DATABASE
,ALTER DATABASE
, andDROP DATABASE
. The database being created, altered, or dropped is considered to be the default database when determining whether to output the statement.
Suppose that the binary log was created by executing these statements using statement-based-logging:
INSERT INTO test.t1 (i) VALUES(100); INSERT INTO db2.t2 (j) VALUES(200); USE test; INSERT INTO test.t1 (i) VALUES(101); INSERT INTO t1 (i) VALUES(102); INSERT INTO db2.t2 (j) VALUES(201); USE db2; INSERT INTO test.t1 (i) VALUES(103); INSERT INTO db2.t2 (j) VALUES(202); INSERT INTO t2 (j) VALUES(203);
mysqlbinlog --database=test does not output the first two
INSERT
statements because there is no default database. It outputs the threeINSERT
statements followingUSE test
, but not the threeINSERT
statements followingUSE db2
.mysqlbinlog --database=db2 does not output the first two
INSERT
statements because there is no default database. It does not output the threeINSERT
statements followingUSE test
, but does output the threeINSERT
statements followingUSE db2
.Row-based logging. mysqlbinlog outputs only entries that change tables belonging to
db_name
. The default database has no effect on this. Suppose that the binary log just described was created using row-based logging rather than statement-based logging. mysqlbinlog --database=test outputs only those entries that modifyt1
in the test database, regardless of whetherUSE
was issued or what the default database is.If a server is running with
binlog_format
set toMIXED
and you want it to be possible to use mysqlbinlog with the--database
option, you must ensure that tables that are modified are in the database selected byUSE
. (In particular, no cross-database updates should be used.)--debug[=
,debug_options
]-# [
debug_options
]Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default isfile_name
''d:t:o,/tmp/mysqlbinlog.trace'
.Print some debugging information when the program exits.
Print debugging information and memory and CPU usage statistics when the program exits.
The client-side authentication plugin to use. See Section 5.5.6, “Pluggable Authentication”.
This option was added in MySQL 5.5.10.
Disable binary logging. This is useful for avoiding an endless loop if you use the
--to-last-log
option and are sending the output to the same MySQL server. This option also is useful when restoring after a crash to avoid duplication of the statements you have logged.This option requires that you have the
SUPER
privilege. It causes mysqlbinlog to include aSET sql_log_bin = 0
statement in its output to disable binary logging of the remaining output. TheSET
statement is ineffective unless you have theSUPER
privilege.--force-read
,-f
With this option, if mysqlbinlog reads a binary log event that it does not recognize, it prints a warning, ignores the event, and continues. Without this option, mysqlbinlog stops if it reads such an event.
--hexdump
,-H
Display a hex dump of the log in comments, as described in Section 4.6.7.1, “mysqlbinlog Hex Dump Format”. The hex output can be helpful for replication debugging.
--host=
,host_name
-h
host_name
Get the binary log from the MySQL server on the given host.
--local-load=
,path
-l
path
Prepare local temporary files for
LOAD DATA INFILE
in the specified directory.ImportantThese temporary files are not automatically removed by mysqlbinlog or any other MySQL program.
--offset=
,N
-o
N
Skip the first
N
entries in the log.--password[=
,password
]-p[
password
]The password to use when connecting to the server. If you use the short option form (
-p
), you cannot have a space between the option and the password. If you omit thepassword
value following the--password
or-p
option on the command line, mysqlbinlog prompts for one.Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
The directory in which to look for plugins. It may be necessary to specify this option if the
--default-auth
option is used to specify an authentication plugin but mysqlbinlog does not find it. See Section 5.5.6, “Pluggable Authentication”.This option was added in MySQL 5.5.10.
--port=
,port_num
-P
port_num
The TCP/IP port number to use for connecting to a remote server.
Deprecated. Use
--start-position
instead.--position
was removed in MySQL 5.5.3.--protocol={TCP|SOCKET|PIPE|MEMORY}
The connection protocol to use for connecting to the server. It is useful when the other connection parameters normally would cause a protocol to be used other than the one you want. For details on the permissible values, see Section 4.2.2, “Connecting to the MySQL Server”.
Read the binary log from a MySQL server rather than reading a local log file. Any connection parameter options are ignored unless this option is given as well. These options are
--host
,--password
,--port
,--protocol
,--socket
, and--user
.This option requires that the remote server be running. It works only for binary log files on the remote server, not relay log files.
--result-file=
,name
-r
name
Direct output to the given file.
Display only those events created by the server having the given server ID.
Use only the first
N
bits of theserver_id
to identify the server. If the binary log was written by a mysqld with server-id-bits set to less than 32 and user data stored in the most significant bit, running mysqlbinlog with--server-id-bits
set to 32 enables this data to be seen.This option is supported only by the versions of mysqlbinlog supplied with the MySQL Cluster distribution, or built from the MySQL Cluster sources.
Add a
SET NAMES
statement to the output to specify the character set to be used for processing log files.charset_name
--short-form
,-s
Display only the statements contained in the log, without any extra information or row-based events. This is for testing only, and should not be used in production systems.
--socket=
,path
-S
path
For connections to
localhost
, the Unix socket file to use, or, on Windows, the name of the named pipe to use.Start reading the binary log at the first event having a timestamp equal to or later than the
datetime
argument. Thedatetime
value is relative to the local time zone on the machine where you run mysqlbinlog. The value should be in a format accepted for theDATETIME
orTIMESTAMP
data types. For example:shell>
mysqlbinlog --start-datetime="2005-12-25 11:25:56" binlog.000003
This option is useful for point-in-time recovery. See Section 6.3, “Пример Backup and Recovery Strategy”.
--start-position=
,N
-j
N
Start reading the binary log at the first event having a position equal to or greater than
N
. This option applies to the first log file named on the command line.This option is useful for point-in-time recovery. See Section 6.3, “Пример Backup and Recovery Strategy”.
Stop reading the binary log at the first event having a timestamp equal to or later than the
datetime
argument. This option is useful for point-in-time recovery. See the description of the--start-datetime
option for information about thedatetime
value.This option is useful for point-in-time recovery. See Section 6.3, “Пример Backup and Recovery Strategy”.
Stop reading the binary log at the first event having a position equal to or greater than
N
. This option applies to the last log file named on the command line.This option is useful for point-in-time recovery. See Section 6.3, “Пример Backup and Recovery Strategy”.
--to-last-log
,-t
Do not stop at the end of the requested binary log from a MySQL server, but rather continue printing until the end of the last binary log. If you send the output to the same MySQL server, this may lead to an endless loop. This option requires
--read-from-remote-server
.--user=
,user_name
-u
user_name
The MySQL user name to use when connecting to a remote server.
--verbose
,-v
Reconstruct row events and display them as commented SQL statements. If this option is given twice, the output includes comments to indicate column data types and some metadata.
For examples that show the effect of
--base64-output
and--verbose
on row event output, see Section 4.6.7.2, “mysqlbinlog Row Event Display”.--version
,-V
Display version information and exit.
You can also set the following variable by using
--
syntax:
var_name
=value
You can pipe the output of mysqlbinlog into the mysql client to execute the events contained in the binary log. This technique is used to recover from a crash when you have an old backup (see Section 6.5, “Point-in-Time (Incremental) Recovery Using the Binary Log”). For example:
shell> mysqlbinlog binlog.000001 | mysql -u root -p
Or:
shell> mysqlbinlog binlog.[0-9]* | mysql -u root -p
You can also redirect the output of mysqlbinlog to a text file instead, if you need to modify the statement log first (for example, to remove statements that you do not want to execute for some reason). After editing the file, execute the statements that it contains by using it as input to the mysql program:
shell>mysqlbinlog binlog.000001 > tmpfile
shell> ...edit tmpfile
... shell>mysql -u root -p < tmpfile
When mysqlbinlog is invoked with the
--start-position
option, it
displays only those events with an offset in the binary log
greater than or equal to a given position (the given position
must match the start of one event). It also has options to stop
and start when it sees an event with a given date and time. This
enables you to perform point-in-time recovery using the
--stop-datetime
option (to
be able to say, for example, “roll forward my databases to
how they were today at 10:30 a.m.”).
If you have more than one binary log to execute on the MySQL server, the safe method is to process them all using a single connection to the server. Here is an example that demonstrates what may be unsafe:
shell>mysqlbinlog binlog.000001 | mysql -u root -p # DANGER!!
shell>mysqlbinlog binlog.000002 | mysql -u root -p # DANGER!!
Processing binary logs this way using multiple connections to
the server causes problems if the first log file contains a
CREATE TEMPORARY
TABLE
statement and the second log contains a
statement that uses the temporary table. When the first
mysql process terminates, the server drops
the temporary table. When the second mysql
process attempts to use the table, the server reports
“unknown table.”
To avoid problems like this, use a single mysql process to execute the contents of all binary logs that you want to process. Here is one way to do so:
shell> mysqlbinlog binlog.000001 binlog.000002 | mysql -u root -p
Another approach is to write all the logs to a single file and then process the file:
shell>mysqlbinlog binlog.000001 > /tmp/statements.sql
shell>mysqlbinlog binlog.000002 >> /tmp/statements.sql
shell>mysql -u root -p -e "source /tmp/statements.sql"
mysqlbinlog can produce output that
reproduces a LOAD
DATA INFILE
operation without the original data file.
mysqlbinlog copies the data to a temporary
file and writes a
LOAD DATA LOCAL
INFILE
statement that refers to the file. The default
location of the directory where these files are written is
system-specific. To specify a directory explicitly, use the
--local-load
option.
Because mysqlbinlog converts
LOAD DATA
INFILE
statements to
LOAD DATA LOCAL
INFILE
statements (that is, it adds
LOCAL
), both the client and the server that
you use to process the statements must be configured with the
LOCAL
capability enabled. See
Section 5.3.5, “Security Issues with LOAD
DATA LOCAL
”.
The temporary files created for
LOAD DATA
LOCAL
statements are not
automatically deleted because they are needed until you
actually execute those statements. You should delete the
temporary files yourself after you no longer need the
statement log. The files can be found in the temporary file
directory and have names like
original_file_name-#-#
.
The --hexdump
option causes
mysqlbinlog to produce a hex dump of the
binary log contents:
shell> mysqlbinlog --hexdump master-bin.000001
The hex output consists of comment lines beginning with
#
, so the output might look like this for the
preceding command:
/*!40019 SET @@session.max_insert_delayed_threads=0*/; /*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/; # at 4 #051024 17:24:13 server id 1 end_log_pos 98 # Position Timestamp Type Master ID Size Master Pos Flags # 00000004 9d fc 5c 43 0f 01 00 00 00 5e 00 00 00 62 00 00 00 00 00 # 00000017 04 00 35 2e 30 2e 31 35 2d 64 65 62 75 67 2d 6c |..5.0.15.debug.l| # 00000027 6f 67 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |og..............| # 00000037 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................| # 00000047 00 00 00 00 9d fc 5c 43 13 38 0d 00 08 00 12 00 |.......C.8......| # 00000057 04 04 04 04 12 00 00 4b 00 04 1a |.......K...| # Start: binlog v 4, server v 5.0.15-debug-log created 051024 17:24:13 # at startup ROLLBACK;
Hex dump output currently contains the elements in the following list. This format is subject to change. (For more information about binary log format, see http://forge.mysql.com/wiki/MySQL_Internals_Binary_Log.)
Position
: The byte position within the log file.Timestamp
: The event timestamp. In the example shown,'9d fc 5c 43'
is the representation of'051024 17:24:13'
in hexadecimal.Type
: The event type code. In the example shown,'0f'
indicates aFORMAT_DESCRIPTION_EVENT
. The following table lists the possible type codes.Type Name Meaning 00
UNKNOWN_EVENT
This event should never be present in the log. 01
START_EVENT_V3
This indicates the start of a log file written by MySQL 4 or earlier. 02
QUERY_EVENT
The most common type of events. These contain statements executed on the master. 03
STOP_EVENT
Indicates that master has stopped. 04
ROTATE_EVENT
Written when the master switches to a new log file. 05
INTVAR_EVENT
Used for AUTO_INCREMENT
values or when theLAST_INSERT_ID()
function is used in the statement.06
LOAD_EVENT
Used for LOAD DATA INFILE
in MySQL 3.23.07
SLAVE_EVENT
Reserved for future use. 08
CREATE_FILE_EVENT
Used for LOAD DATA INFILE
statements. This indicates the start of execution of such a statement. A temporary file is created on the slave. Used in MySQL 4 only.09
APPEND_BLOCK_EVENT
Contains data for use in a LOAD DATA INFILE
statement. The data is stored in the temporary file on the slave.0a
EXEC_LOAD_EVENT
Used for LOAD DATA INFILE
statements. The contents of the temporary file is stored in the table on the slave. Used in MySQL 4 only.0b
DELETE_FILE_EVENT
Rollback of a LOAD DATA INFILE
statement. The temporary file should be deleted on the slave.0c
NEW_LOAD_EVENT
Used for LOAD DATA INFILE
in MySQL 4 and earlier.0d
RAND_EVENT
Used to send information about random values if the RAND()
function is used in the statement.0e
USER_VAR_EVENT
Used to replicate user variables. 0f
FORMAT_DESCRIPTION_EVENT
This indicates the start of a log file written by MySQL 5 or later. 10
XID_EVENT
Event indicating commit of an XA transaction. 11
BEGIN_LOAD_QUERY_EVENT
Used for LOAD DATA INFILE
statements in MySQL 5 and later.12
EXECUTE_LOAD_QUERY_EVENT
Used for LOAD DATA INFILE
statements in MySQL 5 and later.13
TABLE_MAP_EVENT
Information about a table definition. Used in MySQL 5.1.5 and later. 14
PRE_GA_WRITE_ROWS_EVENT
Row data for a single table that should be created. Used in MySQL 5.1.5 to 5.1.17. 15
PRE_GA_UPDATE_ROWS_EVENT
Row data for a single table that needs to be updated. Used in MySQL 5.1.5 to 5.1.17. 16
PRE_GA_DELETE_ROWS_EVENT
Row data for a single table that should be deleted. Used in MySQL 5.1.5 to 5.1.17. 17
WRITE_ROWS_EVENT
Row data for a single table that should be created. Used in MySQL 5.1.18 and later. 18
UPDATE_ROWS_EVENT
Row data for a single table that needs to be updated. Used in MySQL 5.1.18 and later. 19
DELETE_ROWS_EVENT
Row data for a single table that should be deleted. Used in MySQL 5.1.18 and later. 1a
INCIDENT_EVENT
Something out of the ordinary happened. Added in MySQL 5.1.18. Master ID
: The server ID of the master that created the event.Size
: The size in bytes of the event.Master Pos
: The position of the next event in the original master log file.Flags
: 16 flags. Currently, the following flags are used. The others are reserved for future use.Flag Name Meaning 01
LOG_EVENT_BINLOG_IN_USE_F
Log file correctly closed. (Used only in FORMAT_DESCRIPTION_EVENT
.) If this flag is set (if the flags are, for example,'01 00'
) in aFORMAT_DESCRIPTION_EVENT
, the log file has not been properly closed. Most probably this is because of a master crash (for example, due to power failure).02
Reserved for future use. 04
LOG_EVENT_THREAD_SPECIFIC_F
Set if the event is dependent on the connection it was executed in (for example, '04 00'
), for example, if the event uses temporary tables.08
LOG_EVENT_SUPPRESS_USE_F
Set in some circumstances when the event is not dependent on the default database.
The following examples illustrate how
mysqlbinlog displays row events that specify
data modifications. These correspond to events with the
WRITE_ROWS_EVENT
,
UPDATE_ROWS_EVENT
, and
DELETE_ROWS_EVENT
type codes. The
--base64-output=DECODE-ROWS
and --verbose
options may be
used to affect row event output.
Suppose that the server is using row-based binary logging and that you execute the following sequence of statements:
CREATE TABLE t ( id INT NOT NULL, name VARCHAR(20) NOT NULL, date DATE NULL ) ENGINE = InnoDB; START TRANSACTION; INSERT INTO t VALUES(1, 'apple', NULL); UPDATE t SET name = 'pear', date = '2009-01-01' WHERE id = 1; DELETE FROM t WHERE id = 1; COMMIT;
By default, mysqlbinlog displays row events
encoded as base-64 strings using
BINLOG
statements. Omitting
extraneous lines, the output for the row events produced by the
preceding statement sequence looks like this:
shell> mysqlbinlog log_file
...
# at 218
#080828 15:03:08 server id 1 end_log_pos 258 Write_rows: table id 17 flags: STMT_END_F
BINLOG '
fAS3SBMBAAAALAAAANoAAAAAABEAAAAAAAAABHRlc3QAAXQAAwMPCgIUAAQ=
fAS3SBcBAAAAKAAAAAIBAAAQABEAAAAAAAEAA//8AQAAAAVhcHBsZQ==
'/*!*/;
...
# at 302
#080828 15:03:08 server id 1 end_log_pos 356 Update_rows: table id 17 flags: STMT_END_F
BINLOG '
fAS3SBMBAAAALAAAAC4BAAAAABEAAAAAAAAABHRlc3QAAXQAAwMPCgIUAAQ=
fAS3SBgBAAAANgAAAGQBAAAQABEAAAAAAAEAA////AEAAAAFYXBwbGX4AQAAAARwZWFyIbIP
'/*!*/;
...
# at 400
#080828 15:03:08 server id 1 end_log_pos 442 Delete_rows: table id 17 flags: STMT_END_F
BINLOG '
fAS3SBMBAAAALAAAAJABAAAAABEAAAAAAAAABHRlc3QAAXQAAwMPCgIUAAQ=
fAS3SBkBAAAAKgAAALoBAAAQABEAAAAAAAEAA//4AQAAAARwZWFyIbIP
'/*!*/;
To see the row events as comments in the form of
“pseudo-SQL” statements, run
mysqlbinlog with the
--verbose
or
-v
option. The output will contain lines
beginning with ###
:
shell> mysqlbinlog -v log_file
...
# at 218
#080828 15:03:08 server id 1 end_log_pos 258 Write_rows: table id 17 flags: STMT_END_F
BINLOG '
fAS3SBMBAAAALAAAANoAAAAAABEAAAAAAAAABHRlc3QAAXQAAwMPCgIUAAQ=
fAS3SBcBAAAAKAAAAAIBAAAQABEAAAAAAAEAA//8AQAAAAVhcHBsZQ==
'/*!*/;
### INSERT INTO test.t
### SET
### @1=1
### @2='apple'
### @3=NULL
...
# at 302
#080828 15:03:08 server id 1 end_log_pos 356 Update_rows: table id 17 flags: STMT_END_F
BINLOG '
fAS3SBMBAAAALAAAAC4BAAAAABEAAAAAAAAABHRlc3QAAXQAAwMPCgIUAAQ=
fAS3SBgBAAAANgAAAGQBAAAQABEAAAAAAAEAA////AEAAAAFYXBwbGX4AQAAAARwZWFyIbIP
'/*!*/;
### UPDATE test.t
### WHERE
### @1=1
### @2='apple'
### @3=NULL
### SET
### @1=1
### @2='pear'
### @3='2009:01:01'
...
# at 400
#080828 15:03:08 server id 1 end_log_pos 442 Delete_rows: table id 17 flags: STMT_END_F
BINLOG '
fAS3SBMBAAAALAAAAJABAAAAABEAAAAAAAAABHRlc3QAAXQAAwMPCgIUAAQ=
fAS3SBkBAAAAKgAAALoBAAAQABEAAAAAAAEAA//4AQAAAARwZWFyIbIP
'/*!*/;
### DELETE FROM test.t
### WHERE
### @1=1
### @2='pear'
### @3='2009:01:01'
Specify --verbose
or
-v
twice to also display data types and some
metadata for each column. The output will contain an additional
comment following each column change:
shell> mysqlbinlog -vv log_file
...
# at 218
#080828 15:03:08 server id 1 end_log_pos 258 Write_rows: table id 17 flags: STMT_END_F
BINLOG '
fAS3SBMBAAAALAAAANoAAAAAABEAAAAAAAAABHRlc3QAAXQAAwMPCgIUAAQ=
fAS3SBcBAAAAKAAAAAIBAAAQABEAAAAAAAEAA//8AQAAAAVhcHBsZQ==
'/*!*/;
### INSERT INTO test.t
### SET
### @1=1 /* INT meta=0 nullable=0 is_null=0 */
### @2='apple' /* VARSTRING(20) meta=20 nullable=0 is_null=0 */
### @3=NULL /* VARSTRING(20) meta=0 nullable=1 is_null=1 */
...
# at 302
#080828 15:03:08 server id 1 end_log_pos 356 Update_rows: table id 17 flags: STMT_END_F
BINLOG '
fAS3SBMBAAAALAAAAC4BAAAAABEAAAAAAAAABHRlc3QAAXQAAwMPCgIUAAQ=
fAS3SBgBAAAANgAAAGQBAAAQABEAAAAAAAEAA////AEAAAAFYXBwbGX4AQAAAARwZWFyIbIP
'/*!*/;
### UPDATE test.t
### WHERE
### @1=1 /* INT meta=0 nullable=0 is_null=0 */
### @2='apple' /* VARSTRING(20) meta=20 nullable=0 is_null=0 */
### @3=NULL /* VARSTRING(20) meta=0 nullable=1 is_null=1 */
### SET
### @1=1 /* INT meta=0 nullable=0 is_null=0 */
### @2='pear' /* VARSTRING(20) meta=20 nullable=0 is_null=0 */
### @3='2009:01:01' /* DATE meta=0 nullable=1 is_null=0 */
...
# at 400
#080828 15:03:08 server id 1 end_log_pos 442 Delete_rows: table id 17 flags: STMT_END_F
BINLOG '
fAS3SBMBAAAALAAAAJABAAAAABEAAAAAAAAABHRlc3QAAXQAAwMPCgIUAAQ=
fAS3SBkBAAAAKgAAALoBAAAQABEAAAAAAAEAA//4AQAAAARwZWFyIbIP
'/*!*/;
### DELETE FROM test.t
### WHERE
### @1=1 /* INT meta=0 nullable=0 is_null=0 */
### @2='pear' /* VARSTRING(20) meta=20 nullable=0 is_null=0 */
### @3='2009:01:01' /* DATE meta=0 nullable=1 is_null=0 */
You can tell mysqlbinlog to suppress the
BINLOG
statements for row events
by using the
--base64-output=DECODE-ROWS
option. This is similar to
--base64-output=NEVER
but
does not exit with an error if a row event is found. The
combination of
--base64-output=DECODE-ROWS
and --verbose
provides a
convenient way to see row events only as SQL statements:
shell> mysqlbinlog -v --base64-output=DECODE-ROWS log_file
...
# at 218
#080828 15:03:08 server id 1 end_log_pos 258 Write_rows: table id 17 flags: STMT_END_F
### INSERT INTO test.t
### SET
### @1=1
### @2='apple'
### @3=NULL
...
# at 302
#080828 15:03:08 server id 1 end_log_pos 356 Update_rows: table id 17 flags: STMT_END_F
### UPDATE test.t
### WHERE
### @1=1
### @2='apple'
### @3=NULL
### SET
### @1=1
### @2='pear'
### @3='2009:01:01'
...
# at 400
#080828 15:03:08 server id 1 end_log_pos 442 Delete_rows: table id 17 flags: STMT_END_F
### DELETE FROM test.t
### WHERE
### @1=1
### @2='pear'
### @3='2009:01:01'
You should not suppress BINLOG
statements if you intend to re-execute
mysqlbinlog output.
The SQL statements produced by
--verbose
for row events are
much more readable than the corresponding
BINLOG
statements. However, they
do not correspond exactly to the original SQL statements that
generated the events. The following limitations apply:
The original column names are lost and replaced by
@
, whereN
N
is a column number.Character set information is not available in the binary log, which affects string column display:
There is no distinction made between corresponding binary and nonbinary string types (
BINARY
andCHAR
,VARBINARY
andVARCHAR
,BLOB
andTEXT
). The output uses a data type ofSTRING
for fixed-length strings andVARSTRING
for variable-length strings.For multi-byte character sets, the maximum number of bytes per character is not present in the binary log, so the length for string types is displayed in bytes rather than in characters. For example,
STRING(4)
will be used as the data type for values from either of these column types:CHAR(4) CHARACTER SET latin1 CHAR(2) CHARACTER SET ucs2
Due to the storage format for events of type
UPDATE_ROWS_EVENT
,UPDATE
statements are displayed with theWHERE
clause preceding theSET
clause.
Proper interpretation of row events requires the information
from the format description event at the beginning of the binary
log. Because mysqlbinlog does not know in
advance whether the rest of the log contains row events, by
default it displays the format description event using a
BINLOG
statement in the initial
part of the output.
If the binary log is known not to contain any events requiring a
BINLOG
statement (that is, no row
events), the
--base64-output=NEVER
option
can be used to prevent this header from being written.
The MySQL slow query log contains information about queries that take a long time to execute (see Section 5.2.5, “The Slow Query Log”). mysqldumpslow parses MySQL slow query log files and prints a summary of their contents.
Normally, mysqldumpslow groups queries that
are similar except for the particular values of number and
string data values. It “abstracts” these values to
N
and 'S'
when displaying
summary output. The -a
and -n
options can be used to modify value abstracting behavior.
Invoke mysqldumpslow like this:
shell> mysqldumpslow [options
] [log_file
...]
mysqldumpslow supports the following options.
Table 4.12. mysqldumpslow
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
-a | Do not abstract all numbers to N and strings to S | ||||
-n num | Abstract numbers with at least the specified digits | ||||
--debug | debug | Write debugging information | |||
-g pattern | Only consider statements that match the pattern | ||||
--help | Display help message and exit | ||||
-h name | Host name of the server in the log file name | ||||
-i name | Name of the server instance | ||||
-l | Do not subtract lock time from total time | ||||
-r | Reverse the sort order | ||||
-s value | How to sort output | ||||
-t num | Display only first num queries | ||||
--verbose | verbose | Verbose mode |
Display a help message and exit.
Do not abstract all numbers to
N
and strings to'S'
.--debug
,-d
Run in debug mode.
Consider only queries that match the (grep-style) pattern.
Host name of MySQL server for
*-slow.log
file name. The value can contain a wildcard. The default is*
(match all).Name of server instance (if using mysql.server startup script).
Do not subtract lock time from total time.
Abstract numbers with at least
N
digits within names.Reverse the sort order.
How to sort the output. The value of
sort_type
should be chosen from the following list:t
,at
: Sort by query time or average query timel
,al
: Sort by lock time or average lock timer
,ar
: Sort by rows sent or average rows sentc
: Sort by count
By default, mysqldumpslow sorts by average query time (equivalent to
-s at
).Display only the first
N
queries in the output.--verbose
,-v
Verbose mode. Print more information about what the program does.
Пример of usage:
shell> mysqldumpslow
Reading mysql slow query log from /usr/local/mysql/data/mysqld51-apple-slow.log
Count: 1 Time=4.32s (4s) Lock=0.00s (0s) Rows=0.0 (0), root[root]@localhost
insert into t2 select * from t1
Count: 3 Time=2.53s (7s) Lock=0.00s (0s) Rows=0.0 (0), root[root]@localhost
insert into t2 select * from t1 limit N
Count: 3 Time=2.13s (6s) Lock=0.00s (0s) Rows=0.0 (0), root[root]@localhost
insert into t1 select * from t1
mysqlhotcopy is a Perl script that was
originally written and contributed by Tim Bunce. It uses
FLUSH TABLES
,
LOCK TABLES
, and
cp
or scp
to make a
database backup. It is a fast way to make a backup of the
database or single tables, but it can be run only on the same
machine where the database directories are located.
mysqlhotcopy works only for backing up
MyISAM
and ARCHIVE
tables.
It runs on Unix.
To use mysqlhotcopy, you must have read
access to the files for the tables that you are backing up, the
SELECT
privilege for those
tables, the RELOAD
privilege (to
be able to execute FLUSH
TABLES
), and the LOCK
TABLES
privilege (to be able to lock the tables).
shell> mysqlhotcopy db_name
[/path/to/new_directory
]
shell> mysqlhotcopy db_name_1
... db_name_n
/path/to/new_directory
Back up tables in the given database that match a regular expression:
shell> mysqlhotcopy db_name
./regex
/
The regular expression for the table name can be negated by
prefixing it with a tilde (“~
”):
shell> mysqlhotcopy db_name
./~regex
/
mysqlhotcopy supports the following options,
which can be specified on the command line or in the
[mysqlhotcopy]
and
[client]
groups of an option file. For
information about option files, see
Section 4.2.3.3, “Using Option Files”.
Table 4.13. mysqlhotcopy
Options
Format | Option File | Описание | Introduction | Deprecated | Removed |
---|---|---|---|---|---|
--addtodest | addtodest | Do not rename target directory (if it exists); merely add files to it | |||
--allowold | allowold | Do not abort if a target exists; rename it by adding an _old suffix | |||
--checkpoint=db_name.tbl_name | checkpoint | Insert checkpoint entries | |||
--chroot=path | chroot | Base directory of the chroot jail in which mysqld operates | |||
--debug | debug | Write a debugging log | |||
--dryrun | dryrun | Report actions without performing them | |||
--flushlog | flushlog | Flush logs after all tables are locked | |||
--help | Display help message and exit | ||||
--host=host_name | host | Connect to the MySQL server on the given host | |||
--keepold | keepold | Do not delete previous (renamed) target when done | |||
--noindices | noindices | Do not include full index files in the backup | |||
--old_server | old_server | Connect to server that does not support FLUSH TABLES tbl_list WITH READ LOCK | 5.5.3 | ||
--password[=password] | password | The password to use when connecting to the server | |||
--port=port_num | port | The TCP/IP port number to use for the connection | |||
--quiet | quiet | Be silent except for errors | |||
--regexp | regexp | Copy all databases with names that match the given regular expression | |||
--resetmaster | resetmaster | Reset the binary log after locking all the tables | |||
--resetslave | resetslave | Reset the master.info file after locking all the tables | |||
--socket=path | socket | For connections to localhost | |||
--tmpdir=path | tmpdir | The temporary directory | |||
--user=user_name, | user | The MySQL user name to use when connecting to the server |
--help
,-?
Display a help message and exit.
Do not rename target directory (if it exists); merely add files to it.
Do not abort if a target exists; rename it by adding an
_old
suffix.Insert checkpoint entries into the specified database
db_name
and tabletbl_name
.Base directory of the chroot jail in which mysqld operates. The
path
value should match that of the--chroot
option given to mysqld.Enable debug output.
--dryrun
,-n
Report actions without performing them.
Flush logs after all tables are locked.
--host=
,host_name
-h
host_name
The host name of the local host to use for making a TCP/IP connection to the local server. By default, the connection is made to
localhost
using a Unix socket file.Do not delete previous (renamed) target when done.
The method for copying files (
cp
orscp
). The default iscp
.Do not include full index files for
MyISAM
tables in the backup. This makes the backup smaller and faster. The indexes for reloaded tables can be reconstructed later with myisamchk -rq.--password=
,password
-p
password
The password to use when connecting to the server. The password value is not optional for this option, unlike for other MySQL programs.
Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
--port=
,port_num
-P
port_num
The TCP/IP port number to use when connecting to the local server.
As of MySQL 5.5.3, mysqlhotcopy uses
FLUSH TABLES
to flush and lock tables. Use thetbl_list
WITH READ LOCK--old_server
option if the server is older than 5.5.3, which is when that statement was introduced. This option was added in MySQL 5.5.3.--quiet
,-q
Be silent except for errors.
--record_log_pos=
db_name
.tbl_name
Record master and slave status in the specified database
db_name
and tabletbl_name
.Copy all databases with names that match the given regular expression.
Reset the binary log after locking all the tables.
Reset the
master.info
file after locking all the tables.--socket=
,path
-S
path
The Unix socket file to use for connections to
localhost
.The suffix to use for names of copied databases.
The temporary directory. The default is
/tmp
.--user=
,user_name
-u
user_name
The MySQL user name to use when connecting to the server.
Use perldoc
for additional
mysqlhotcopy documentation, including
information about the structure of the tables needed for the
--checkpoint
and
--record_log_pos
options:
shell> perldoc mysqlhotcopy
mysql_convert_table_format converts the
tables in a database to use a particular storage engine
(MyISAM
by default).
mysql_convert_table_format is written in Perl
and requires that the DBI
and
DBD::mysql
Perl modules be installed (see
Section 2.13, “Perl Installation Notes”).
Invoke mysql_convert_table_format like this:
shell> mysql_convert_table_format [options
]db_name
The db_name
argument indicates the
database containing the tables to be converted.
mysql_convert_table_format supports the options described in the following list.
Display a help message and exit.
Continue even if errors occur.
Connect to the MySQL server on the given host.
The password to use when connecting to the server. Note that the password value is not optional for this option, unlike for other MySQL programs.
Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
The TCP/IP port number to use for the connection.
For connections to
localhost
, the Unix socket file to use.Specify the storage engine that the tables should be converted to use. The default is
MyISAM
if this option is not given.The MySQL user name to use when connecting to the server.
Verbose mode. Print more information about what the program does.
Display version information and exit.
mysql_find_rows reads files containing SQL
statements and extracts statements that match a given regular
expression or that contain USE
or
db_name
SET
statements. The utility was written for use with update log
files (as used prior to MySQL 5.0) and as such expects
statements to be terminated with semicolon
(;
) characters. It may be useful with other
files that contain SQL statements as long as statements are
terminated with semicolons.
Invoke mysql_find_rows like this:
shell> mysql_find_rows [options
] [file_name
...]
Each file_name
argument should be the
name of file containing SQL statements. If no file names are
given, mysql_find_rows reads the standard
input.
Examples:
mysql_find_rows --regexp=problem_table --rows=20 < update.log mysql_find_rows --regexp=problem_table update-log.1 update-log.2
mysql_find_rows supports the following options:
Display a help message and exit.
Display queries that match the pattern.
Quit after displaying
N
queries.Do not include
USE
statements in the output.db_name
Start output from this row.
mysql_fix_extensions converts the extensions
for MyISAM
(or ISAM
) table
files to their canonical forms. It looks for files with
extensions matching any lettercase variant of
.frm
, .myd
,
.myi
, .isd
, and
.ism
and renames them to have extensions of
.frm
, .MYD
,
.MYI
, .ISD
, and
.ISM
, respectively. This can be useful
after transferring the files from a system with case-insensitive
file names (such as Windows) to a system with case-sensitive
file names.
Invoke mysql_fix_extensions like this, where
data_dir
is the path name to the
MySQL data directory.
shell> mysql_fix_extensions data_dir
mysql_setpermission is a Perl script that was
originally written and contributed by Luuk de Boer. It
interactively sets permissions in the MySQL grant tables.
mysql_setpermission is written in Perl and
requires that the DBI
and
DBD::mysql
Perl modules be installed (see
Section 2.13, “Perl Installation Notes”).
Invoke mysql_setpermission like this:
shell> mysql_setpermission [options
]
options
should be either
--help
to display
the help message, or options that indicate how to connect to the
MySQL server. The account used when you connect determines which
permissions you have when attempting to modify existing
permissions in the grant tables.
mysql_setpermissions also reads options from
the [client]
and [perl]
groups in the .my.cnf
file in your home
directory, if the file exists.
mysql_setpermission supports the following options:
Display a help message and exit.
Connect to the MySQL server on the given host.
The password to use when connecting to the server. Note that the password value is not optional for this option, unlike for other MySQL programs.
Specifying a password on the command line should be considered insecure. See Section 5.3.2.2, “End-User Guidelines for Password Security”. You can use an option file to avoid giving the password on the command line.
The TCP/IP port number to use for the connection.
For connections to
localhost
, the Unix socket file to use.The MySQL user name to use when connecting to the server.
mysql_waitpid signals a process to terminate
and waits for the process to exit. It uses the
kill()
system call and Unix signals, so it
runs on Unix and Unix-like systems.
Invoke mysql_waitpid like this:
shell> mysql_waitpid [options
] pid
wait_time
mysql_waitpid sends signal 0 to the process
identified by pid
and waits up to
wait_time
seconds for the process to
terminate. pid
and
wait_time
must be positive integers.
If process termination occurs within the wait time or the process does not exist, mysql_waitpid returns 0. Otherwise, it returns 1.
If the kill()
system call cannot handle
signal 0, mysql_waitpid() uses signal 1
instead.
mysql_waitpid supports the following options:
mysql_zap kills processes that match a pattern. It uses the ps command and Unix signals, so it runs on Unix and Unix-like systems.
Invoke mysql_zap like this:
shell> mysql_zap [-signal
] [-?Ift] pattern
A process matches if its output line from the
ps command contains the pattern. By default,
mysql_zap asks for confirmation for each
process. Respond y
to kill the process, or
q
to exit mysql_zap. For
any other response, mysql_zap does not
attempt to kill the process.
If the -
option is given, it specifies the name or number of the signal
to send to each process. Otherwise, mysql_zap
tries first with signal
TERM
(signal 15) and then
with KILL
(signal 9).
mysql_zap supports the following additional options:
This section describes some utilities that you may find useful when developing MySQL programs.
In shell scripts, you can use the
my_print_defaults program to parse option files
and see what options would be used by a given program. The following
example shows the output that my_print_defaults
might produce when asked to show the options found in the
[client]
and [mysql]
groups:
shell> my_print_defaults client mysql
--port=3306
--socket=/tmp/mysql.sock
--no-auto-rehash
Note for developers: Option file handling is implemented in the C client library simply by processing all options in the appropriate group or groups before any command-line arguments. This works well for programs that use the last instance of an option that is specified multiple times. If you have a C or C++ program that handles multiply specified options this way but that doesn't read option files, you need add only two lines to give it that capability. Check the source code of any of the standard MySQL clients to see how to do this.
Several other language interfaces to MySQL are based on the C client library, and some of them provide a way to access option file contents. These include Perl and Python. For details, see the documentation for your preferred interface.
Initially, the MySQL C API was developed to be very similar to that for the mSQL database system. Because of this, mSQL programs often can be converted relatively easily for use with MySQL by changing the names of the C API functions.
The msql2mysql utility performs the conversion of mSQL C API function calls to their MySQL equivalents. msql2mysql converts the input file in place, so make a copy of the original before converting it. For example, use msql2mysql like this:
shell>cp client-prog.c client-prog.c.orig
shell>msql2mysql client-prog.c
client-prog.c converted
Then examine client-prog.c
and make any
post-conversion revisions that may be necessary.
msql2mysql uses the replace utility to make the function name substitutions. See Section 4.8.2, “replace — A String-Replacement Utility”.
mysql_config provides you with useful information for compiling your MySQL client and connecting it to MySQL.
mysql_config supports the following options.
Compiler flags to find include files and critical compiler flags and defines used when compiling the
libmysqlclient
library. The options returned are tied to the specific compiler that was used when the library was created and might clash with the settings for your own compiler. Use--include
for more portable options that contain only include paths.Compiler options to find MySQL include files.
Libraries and options required to link with the MySQL embedded server.
Libraries and options required to link with the MySQL client library.
Libraries and options required to link with the thread-safe MySQL client library.
The default plugin directory path name, defined when configuring MySQL.
The default TCP/IP port number, defined when configuring MySQL.
The default Unix socket file, defined when configuring MySQL.
Version number for the MySQL distribution.
If you invoke mysql_config with no options, it displays a list of all options that it supports, and their values:
shell> mysql_config
Usage: /usr/local/mysql/bin/mysql_config [options]
Options:
--cflags [-I/usr/local/mysql/include/mysql -mcpu=pentiumpro]
--include [-I/usr/local/mysql/include/mysql]
--libs [-L/usr/local/mysql/lib/mysql -lmysqlclient -lz
-lcrypt -lnsl -lm -L/usr/lib -lssl -lcrypto]
--libs_r [-L/usr/local/mysql/lib/mysql -lmysqlclient_r
-lpthread -lz -lcrypt -lnsl -lm -lpthread]
--socket [/tmp/mysql.sock]
--port [3306]
--version [4.0.16]
--libmysqld-libs [-L/usr/local/mysql/lib/mysql -lmysqld -lpthread -lz
-lcrypt -lnsl -lm -lpthread -lrt]
You can use mysql_config within a command line to include the value that it displays for a particular option. For example, to compile a MySQL client program, use mysql_config as follows:
shell>CFG=/usr/local/mysql/bin/mysql_config
shell>sh -c "gcc -o progname `$CFG --include` progname.c `$CFG --libs`"
When you use mysql_config this way, be sure
to invoke it within backtick
(“`
”) characters. That tells the
shell to execute it and substitute its output into the
surrounding command.
my_print_defaults displays the options that
are present in option groups of option files. The output
indicates what options will be used by programs that read the
specified option groups. For example, the
mysqlcheck program reads the
[mysqlcheck]
and [client]
option groups. To see what options are present in those groups
in the standard option files, invoke
my_print_defaults like this:
shell> my_print_defaults mysqlcheck client
--user=myusername
--password=secret
--host=localhost
The output consists of options, one per line, in the form that they would be specified on the command line.
my_print_defaults supports the following options.
--help
,-?
Display a help message and exit.
--config-file=
,file_name
--defaults-file=
,file_name
-c
file_name
Read only the given option file.
--debug=
,debug_options
-#
debug_options
Write a debugging log. A typical
debug_options
string is'd:t:o,
. The default isfile_name
''d:t:o,/tmp/my_print_defaults.trace'
.--defaults-extra-file=
,file_name
--extra-file=
,file_name
-e
file_name
Read this option file after the global option file but (on Unix) before the user option file.
--defaults-group-suffix=
,suffix
-g
suffix
In addition to the groups named on the command line, read groups that have the given suffix.
--no-defaults
,-n
Return an empty string.
--verbose
,-v
Verbose mode. Print more information about what the program does.
--version
,-V
Display version information and exit.
resolve_stack_dump resolves a numeric stack dump to symbols.
Invoke resolve_stack_dump like this:
shell> resolve_stack_dump [options
] symbols_file
[numeric_dump_file
]
The symbols file should include the output from the nm --numeric-sort mysqld command. The numeric dump file should contain a numeric stack track from mysqld. If no numeric dump file is named on the command line, the stack trace is read from the standard input.
resolve_stack_dump supports the following options.
--help
,-h
Display a help message and exit.
--numeric-dump-file=
,file_name
-n
file_name
Read the stack trace from the given file.
--symbols-file=
,file_name
-s
file_name
Use the given symbols file.
--version
,-V
Display version information and exit.
For most system errors, MySQL displays, in addition to an internal text message, the system error code in one of the following styles:
message ... (errno: #) message ... (Errcode: #)
You can find out what the error code means by examining the documentation for your system or by using the perror utility.
perror prints a description for a system error code or for a storage engine (table handler) error code.
Invoke perror like this:
shell> perror [options
] errorcode
...
Пример:
shell> perror 13 64
OS error code 13: Permission denied
OS error code 64: Machine is not on the network
To obtain the error message for a MySQL Cluster error code,
invoke perror with the
--ndb
option:
shell> perror --ndb errorcode
Note that the meaning of system error messages may be dependent on your operating system. A given error code may mean different things on different operating systems.
perror supports the following options.
The replace utility program changes strings in place in files or on the standard input.
Invoke replace in one of the following ways:
shell>replace
shell>from
to
[from
to
] ... --file_name
[file_name
] ...replace
from
to
[from
to
] ... <file_name
from
represents a string to look for
and to
represents its replacement.
There can be one or more pairs of strings.
Use the --
option to indicate where the
string-replacement list ends and the file names begin. In this
case, any file named on the command line is modified in place,
so you may want to make a copy of the original before converting
it. replace
prints a message
indicating which of the input files it actually modifies.
If the --
option is not given,
replace reads the standard input and writes
to the standard output.
replace uses a finite state machine to match
longer strings first. It can be used to swap strings. For
example, the following command swaps a
and
b
in the given files,
file1
and file2
:
shell> replace a b b a -- file1 file2 ...
The replace program is used by msql2mysql. See Section 4.7.1, “msql2mysql — Convert mSQL Programs for Use with MySQL”.
replace supports the following options.