oci_connect
(PHP 5, PECL OCI8 >= 1.1.0)
oci_connect — Connect to an Oracle database
Description
$username
, string $password
[, string $connection_string
[, string $character_set
[, int $session_mode
]]] )Returns a connection identifier needed for most other OCI8 operations.
See Connection Handling for general information on connection management and connection pooling.
From PHP 5.1.2 (PECL OCI8 1.1) oci_close() can be used to close the connection.
The second and subsequent calls to oci_connect() with the same parameters will return the connection handle returned from the first call. This means that transactions in one handle are also in the other handles, because they use the same underlying database connection. If two handles need to be transactionally isolated from each other, use oci_new_connect() instead.
Parameters
-
username -
The Oracle user name.
-
password -
The password for
username. -
connection_string -
Contains the Oracle instance to connect to. It can be an » Easy Connect string, or a Connect Name from the tnsnames.ora file, or the name of a local Oracle instance.
If not specified, PHP uses environment variables such as
TWO_TASK(on Linux) orLOCAL(on Windows) andORACLE_SIDto determine the Oracle instance to connect to.To use the Easy Connect naming method, PHP must be linked with Oracle 10g or greater Client libraries. The Easy Connect string for Oracle 10g is of the form: [//]host_name[:port][/service_name]. From Oracle 11g, the syntax is: [//]host_name[:port][/service_name][:server_type][/instance_name]. Service names can be found by running the Oracle utility lsnrctl status on the database server machine.
The tnsnames.ora file can be in the Oracle Net search path, which includes $ORACLE_HOME/network/admin and /etc. Alternatively set TNS_ADMIN so that $TNS_ADMIN/tnsnames.ora is read. Make sure the web daemon has read access to the file.
-
character_set -
Determines the character set used by the Oracle Client libraries. The character set does not need to match the character set used by the database. If it doesn't match, Oracle will do its best to convert data to and from the database character set. Depending on the character sets this may not give usable results. Conversion also adds some time overhead.
If not specified, the Oracle Client libraries determine a character set from the
NLS_LANGenvironment variable.Passing this parameter can reduce the time taken to connect.
-
session_mode -
This parameter is available since version PHP 5 (PECL OCI8 1.1) and accepts the following values:
OCI_DEFAULT,OCI_SYSOPERandOCI_SYSDBA. If eitherOCI_SYSOPERorOCI_SYSDBAwere specified, this function will try to establish privileged connection using external credentials. Privileged connections are disabled by default. To enable them you need to set oci8.privileged_connect to On.PHP 5.3 (PECL OCI8 1.3.4) introduced the
OCI_CRED_EXTmode value. This tells Oracle to use External or OS authentication, which must be configured in the database. TheOCI_CRED_EXTflag can only be used with username of "/" and a empty password. oci8.privileged_connect may be On or Off.OCI_CRED_EXTmay be combined with theOCI_SYSOPERorOCI_SYSDBAmodes.OCI_CRED_EXTis not supported on Windows for security reasons.
Return Values
Returns a connection identifier or FALSE on error.
Examples
Example #1 Basic oci_connect() using Easy Connect syntax
<?php
// Connects to the XE service (i.e. database) on the "localhost" machine
$conn = oci_connect('hr', 'welcome', 'localhost/XE');
if (!$conn) {
$e = oci_error();
trigger_error(htmlentities($e['message'], ENT_QUOTES), E_USER_ERROR);
}
$stid = oci_parse($conn, 'SELECT * FROM employees');
oci_execute($stid);
echo "<table border='1'>\n";
while ($row = oci_fetch_array($stid, OCI_ASSOC+OCI_RETURN_NULLS)) {
echo "<tr>\n";
foreach ($row as $item) {
echo " <td>" . ($item !== null ? htmlentities($item, ENT_QUOTES) : " ") . "</td>\n";
}
echo "</tr>\n";
}
echo "</table>\n";
?>
Example #2 Basic oci_connect() using a Network Connect name
<?php
// Connects to the MYDB database described in tnsnames.ora file,
// One example tnsnames.ora entry for MYDB could be:
// MYDB =
// (DESCRIPTION =
// (ADDRESS = (PROTOCOL = TCP)(HOST = mymachine.oracle.com)(PORT = 1521))
// (CONNECT_DATA =
// (SERVER = DEDICATED)
// (SERVICE_NAME = XE)
// )
// )
$conn = oci_connect('hr', 'welcome', 'MYDB');
if (!$conn) {
$e = oci_error();
trigger_error(htmlentities($e['message'], ENT_QUOTES), E_USER_ERROR);
}
$stid = oci_parse($conn, 'SELECT * FROM employees');
oci_execute($stid);
echo "<table border='1'>\n";
while ($row = oci_fetch_array($stid, OCI_ASSOC+OCI_RETURN_NULLS)) {
echo "<tr>\n";
foreach ($row as $item) {
echo " <td>" . ($item !== null ? htmlentities($item, ENT_QUOTES) : " ") . "</td>\n";
}
echo "</tr>\n";
}
echo "</table>\n";
?>
Example #3 oci_connect() with an explicit character set
<?php
$conn = oci_connect('hr', 'welcome', 'localhost/XE', 'AL32UTF8');
if (!$conn) {
$e = oci_error();
trigger_error(htmlentities($e['message'], ENT_QUOTES), E_USER_ERROR);
}
$stid = oci_parse($conn, 'SELECT * FROM employees');
oci_execute($stid);
echo "<table border='1'>\n";
while ($row = oci_fetch_array($stid, OCI_ASSOC+OCI_RETURN_NULLS)) {
echo "<tr>\n";
foreach ($row as $item) {
echo " <td>" . ($item !== null ? htmlentities($item, ENT_QUOTES) : " ") . "</td>\n";
}
echo "</tr>\n";
}
echo "</table>\n";
?>
Example #4 Using multiple calls to oci_connect()
<?php
$c1 = oci_connect("hr", "welcome", 'localhost/XE');
$c2 = oci_connect("hr", "welcome", 'localhost/XE');
// Both $c1 and $c2 show the same PHP resource id meaning they use the
// same underlying database connection
echo "c1 is $c1<br>\n";
echo "c2 is $c2<br>\n";
function create_table($conn)
{
$stmt = oci_parse($conn, "create table hallo (test varchar2(64))");
oci_execute($stmt);
echo "Created table<br>\n";
}
function drop_table($conn)
{
$stmt = oci_parse($conn, "drop table hallo");
oci_execute($stmt);
echo "Dropped table<br>\n";
}
function insert_data($connname, $conn)
{
$stmt = oci_parse($conn, "insert into hallo
values(to_char(sysdate,'DD-MON-YY HH24:MI:SS'))");
oci_execute($stmt, OCI_DEFAULT);
echo "$connname inserted row without committing<br>\n";
}
function rollback($connname, $conn)
{
oci_rollback($conn);
echo "$connname rollback<br>\n";
}
function select_data($connname, $conn)
{
$stmt = oci_parse($conn, "select * from hallo");
oci_execute($stmt, OCI_DEFAULT);
echo "$connname ----selecting<br>\n";
while (oci_fetch($stmt)) {
echo " " . oci_result($stmt, "TEST") . "<br>\n";
}
echo "$connname ----done<br>\n";
}
create_table($c1);
insert_data('c1', $c1); // Insert a row using c1
sleep(2); // sleep to show a different timestamp for the 2nd row
insert_data('c2', $c2); // Insert a row using c2
select_data('c1', $c1); // Results of both inserts are returned
select_data('c2', $c2); // Results of both inserts are returned
rollback('c1', $c1); // Rollback using c1
select_data('c1', $c1); // Both inserts have been rolled back
select_data('c2', $c2);
drop_table($c1);
// Closing one of the connections makes the PHP variable unusable, but
// the other could be used
oci_close($c1);
echo "c1 is $c1<br>\n";
echo "c2 is $c2<br>\n";
// Output is:
// c1 is Resource id #5
// c2 is Resource id #5
// Created table
// c1 inserted row without committing
// c2 inserted row without committing
// c1 ----selecting
// 09-DEC-09 12:14:43
// 09-DEC-09 12:14:45
// c1 ----done
// c2 ----selecting
// 09-DEC-09 12:14:43
// 09-DEC-09 12:14:45
// c2 ----done
// c1 rollback
// c1 ----selecting
// c1 ----done
// c2 ----selecting
// c2 ----done
// Dropped table
// c1 is
// c2 is Resource id #5
?>
Notes
Note:
An incorrectly installed or configured OCI8 extension will often manifest itself as a connection problem or error. See Installing/Configuring for troubleshooting information.
See Also
- oci_pconnect() - Connect to an Oracle database using a persistent connection
- oci_new_connect() - Connect to the Oracle server using a unique connection
- oci_close() - Closes an Oracle connection
- PHP Руководство
- Функции по категориям
- Индекс функций
- Справочник функций
- Расширения для работы с базами данных
- Расширения для работы с базами данных отдельных производителей
- Oracle OCI8
- oci_bind_array_by_name
- oci_bind_by_name
- oci_cancel
- oci_client_version
- oci_close
- oci_commit
- oci_connect
- oci_define_by_name
- oci_error
- oci_execute
- oci_fetch_all
- oci_fetch_array
- oci_fetch_assoc
- oci_fetch_object
- oci_fetch_row
- oci_fetch
- oci_field_is_null
- oci_field_name
- oci_field_precision
- oci_field_scale
- oci_field_size
- oci_field_type_raw
- oci_field_type
- oci_free_descriptor
- oci_free_statement
- oci_get_implicit_resultset
- oci_internal_debug
- oci_lob_copy
- oci_lob_is_equal
- oci_new_collection
- oci_new_connect
- oci_new_cursor
- oci_new_descriptor
- oci_num_fields
- oci_num_rows
- oci_parse
- oci_password_change
- oci_pconnect
- oci_result
- oci_rollback
- oci_server_version
- oci_set_action
- oci_set_client_identifier
- oci_set_client_info
- oci_set_edition
- oci_set_module_name
- oci_set_prefetch
- oci_statement_type
Коментарии
If your oracle database is on a remote system within your local network and you don't want to worry about the tnsnames file you can try this.
$db = "(DESCRIPTION=(ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = 192.168.XX.XXX)(PORT = 1521)))(CONNECT_DATA=(SID=XXXX)))";
$c1 = ocilogon("name","password",$db);
Hope this helps someone.
There is a useful solution to the problem of securing connection information in the PHP Cookbook (O'Reilly) by David Sklar and Adam Trachtenberg. They propose using 'SetEnv' in the Apache configuration and then accessing the values from within a script using $_SERVER.
Unfortunately using the 'SetEnv' solution exposes your connection information to all users of that virtual host. If they run phpinfo.php or display $_SERVER, I found that they will see the password from any file under the root of that virtual host.
To restrict exposure to a particular directory or specific file:
1. First put an 'Include' to the secret file in httpd.conf. For example:
Include "/web/private/secret.txt"
2. In the password file, use the 'SetEnvIf' directive to enable the Environment variables by directory only or within a specific file. For example:
- For all files in the directory:
SetEnvIf Request_URI "/path/to/my/directory" ORACLE_PASS=5gHj790j
- For a specific file in the directory
SetEnvIf Request_URI "/path/to/my/directory/connection.oracle.php" ORACLE_PASS=5gHj790j
When you are using Oracle 9.2+ I would say that you MUST use the CHARSET parameter.
Of course, you will not notice it until there is accented character... so just specify it and you will avoid a big headache.
So for example here is our Oracle internal conf:
select * from nls_database_parameters;
PARAMETER VALUE
------------------------------ ----------------------------------------
…
NLS_LANGUAGE AMERICAN
NLS_TERRITORY AMERICA
NLS_ISO_CURRENCY AMERICA
NLS_CHARACTERSET WE8ISO8859P15
…
And there our oci_connect call:
$dbch=ocilogon($user,$pass,$connectString,"WE8ISO8859P15");
Without that, you will get question mark (inversed), squares… instead of most accented character.
Don’t forget to use that for writing as well as for reading.
If you want to specify a connection timeout in case there is network problem, you can edit the client side (e.g. PHP side) sqlnet.ora file and set SQLNET.OUTBOUND_CONNECT_TIMEOUT. This sets the upper time limit for establishing a connection right through to the DB, including the time for attempts to connect to other services. It is available from Oracle 10.2.0.3 onwards.
In Oracle 11.1, a slightly lighter-weight solution TCP.CONNECT_TIMEOUT was introduced. It also is a sqlnet.ora parameter. It bounds just the TCP connection establishment time, which is mostly where connection problem are seen.
The client sqlnet.ora file should be put in the same directory as the tnsnames.ora file.
ONE ALTERNATIVE OF CONNECT IN ORACLE RAC "Real Application Clusters"
<?php
$dbstr ="(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST =ip1)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = banco)
(INSTANCE_NAME = banco1)))";
$dbstr1 ="(DESCRIPTION =(ADDRESS = (PROTOCOL = TCP)(HOST =ip2)(PORT = 1521))
(CONNECT_DATA =
(SERVER = DEDICATED)
(SERVICE_NAME = banco)
(INSTANCE_NAME = banco2)))";
if(!@($conn = oci_connect('user','password',$dbstr1)))
{ $conn = oci_connect('user','password',$dbstr) or die (ocierror()); }
?>
When using the OCI_CRED_EXT in php
if the ENV $ORACLE_SID is set the DB does not need to be specified explicitly and the connection will fail unless you provide a NULL DB value when creating the connection.
The $ORACLE_SID trumps the TNS name look up for the connection. So even a manual connection string in the DB parameter will fail.
So when the $ORACLE_SID Env is set a NULL passed instead of the DB name connects successfully.
Hope this saves some hair pulling when moving to %.3 and OS Authentications
Regarding the following statement in the documentation:
"The second and subsequent calls to oci_connect() with the same parameters will return the connection handle returned from the first call."
There's one caveat here. Subsequent calls to oci_connect() will only return the same connection handle as the first call as long as a reference is held to the original handle.
For example, the following code will generate *one* connection handle:
<?php
$dbh = oci_connect($username, $password, $conn_info);
// Do stuff
$dbh = oci_connect$username, $password, $conn_info);
// Do more stuff
The follow code will generate *two* connection handles:
getData();
// Do stuff
getData();
// Do more stuff
getData() {
$dbh = oci_connect($username, $password, $conn_info);
// Do stuff
}
?>
This is the result of PHP garbage collecting the handle at the end of the method scope.
If you want to isolate your DB layer through function calls but still want to leverage the fact that oci_connect can return the same handle, just keep a reference to the handle like so:
<?php
getData($username, $password, $conn_info) {
$dbh = oci_connect($username, $password, $conn_info);
$key = hash('md5', "$username|$password|$conn_info");
$GLOBALS[$key] = $dbh;
// Do stuff
}
?>
I originally logged this as a bug but apparently this is the expected behaviour, likely because oci_close($dbh) just calls unset($dbh).
Using ldap for Oracle name resolution:
The web server needs the environmental variable TNS_ADMIN='Directory of tnsname.ora'. I use '/etc/tns_admin'. Confirm using the phpinfo() function.
There are three files needed in the TNS_ADMIN location: tnsnames.ora, sqlnet.ora and ldap.ora. If you are only using ldap, tnsnames.ora is not needed.
To sqlnet.ora add:
NAMES.DIRECTORY_PATH=(TNSNAMES,LDAP)
To ldap.ora add:
DIRECTORY_SERVERS=(ldap_fqdn_hostname:1575)
DEFAULT_ADMIN_CONTEXT=""
DIRECTORY_SERVER_TYPE=OID
For a quick and dirty ldap tnsnames server use tnsManager by Dave Berry. Oracle OID or Openldap can used, but are complicated to setup. tnsManager is a no brainer. The default port is 1575.
The order of values in NAMES.DIRECTORY_PATH from sqlnet.ora determines which look up 'adapter' is used first, in this case it is tnsnames.ora file and then ldap. I use ldap for general consumption and tnsnames.ora file to override ldap or entries that are not for general consumption.
If you have the full Oracle client you have tnsping. 'tnsping ORACLE_SID' will tell you what adapter you are using: 'Used LDAP adapter to resolve the alias'.
<?php
echo system("/PATH/tnsping ".$ORACLE_SID." 2>&1")."<br />";
echo 'TNS_ADMIN='.getenv('TNS_ADMIN');
?>
ISSUE:
For some reason PHP tries the HOSTNAME adapter first, and if the database name resolves in DNS, it will try connecting using the database name as the hostname with no SID or SERVICE_NAME defined. All other Oracle clients I have used will not try the HOSTNAME adapter unless it is listed in NAMES.DIRECTORY_PATH.
I have heard that LDAP look up does not work with older instantclients.
Using ldap for Oracle name resolution:
The web server will need the environmental variable TNS_ADMIN='Directory of tnsname.ora' unless the default location is used. I use '/etc/tns_admin'. Confirm using the phpinfo().
There are three files needed in the TNS_ADMIN location: tnsnames.ora, sqlnet.ora and ldap.ora. If you are only using ldap, tnsnames.ora is not needed.
To sqlnet.ora add:
NAMES.DIRECTORY_PATH=(TNSNAMES,LDAP)
To ldap.ora add:
DIRECTORY_SERVERS=(ldap_server_fqdn:port)
DEFAULT_ADMIN_CONTEXT=""
DIRECTORY_SERVER_TYPE=OID
For a quick and dirty ldap tnsnames server use tnsManager by Dave Berry. Oracle OID or Openldap can used, but are complicated to setup. tnsManager is a no brainer. The quick part: give it a tnsnames.ora file and start it up. The dirty parts: I can't get Toad and SQLDeveloper to work with it, it ignores the domain and it is no longer being maintained.
The order of values in NAMES.DIRECTORY_PATH in sqlnet.ora determines which look up 'adapter' is used, in this case it is tnsnames.ora file and then ldap. I use ldap for general consumption and tnsnames.ora file to override ldap or entries that are not for general consumption.
If you have the full Oracle client you have tnsping. 'tnsping ORACLE_SID' will tell you what adapter you are using: 'Used LDAP adapter to resolve the alias'.
<?php
echo system("/PATH/tnsping ".$ORACLE_SID." 2>&1")."<br />";
echo 'TNS_ADMIN='.getenv('TNS_ADMIN');
?>
ISSUE:
If connecting with only ORACLE_SID and not ORACLE_SID.DB_DOMAIN, the value of NAMES.DEFAULT_DOMAIN from sqlnet.ora is appended, then for some reason PHP tries the HOSTNAME adapter, and if the database name resolves in DNS, it will fail connecting using the database name as the hostname, because neither SID nor SERVICE_NAME are defined.
If using tnsManager append '.ANY_DOMAIN' to $ORACLE_SID to hack around the issue above.
I have tested with:
11.1.0.7 full client and PHP 5.1.6
11.2.0.2 full client and PHP 5.4.11
I have heard that LDAP lookup does not work with older instantclients.