odbc_pconnect
(PHP 4, PHP 5)
odbc_pconnect — Open a persistent database connection
Description
resource odbc_pconnect
( string
$dsn
, string $user
, string $password
[, int $cursor_type
] )Opens a persistent database connection.
This function is much like
odbc_connect(), except that the connection is
not really closed when the script has finished. Future requests
for a connection with the same dsn,
user, password
combination (via odbc_connect() and
odbc_pconnect()) can reuse the persistent
connection.
Parameters
See odbc_connect() for details.
Return Values
Returns an ODBC connection id or 0 (FALSE) on
error.
Notes
Note: Persistent connections have no effect if PHP is used as a CGI program.
- PHP Руководство
- Функции по категориям
- Индекс функций
- Справочник функций
- Расширения для работы с базами данных
- Уровни абстракции
- ODBC (Unified)
- odbc_autocommit
- odbc_binmode
- odbc_close_all
- odbc_close
- odbc_columnprivileges
- odbc_columns
- odbc_commit
- odbc_connect
- odbc_cursor
- odbc_data_source
- odbc_do
- odbc_error
- odbc_errormsg
- odbc_exec
- odbc_execute
- odbc_fetch_array
- odbc_fetch_into
- odbc_fetch_object
- odbc_fetch_row
- odbc_field_len
- odbc_field_name
- odbc_field_num
- odbc_field_precision
- odbc_field_scale
- odbc_field_type
- odbc_foreignkeys
- odbc_free_result
- odbc_gettypeinfo
- odbc_longreadlen
- odbc_next_result
- odbc_num_fields
- odbc_num_rows
- odbc_pconnect
- odbc_prepare
- odbc_primarykeys
- odbc_procedurecolumns
- odbc_procedures
- odbc_result_all
- odbc_result
- odbc_rollback
- odbc_setoption
- odbc_specialcolumns
- odbc_statistics
- odbc_tableprivileges
- odbc_tables
Коментарии
The following constants are defined for cursortype:
- SQL_CUR_USE_IF_NEEDED
- SQL_CUR_USE_ODBC
- SQL_CUR_USE_DRIVER
- SQL_CUR_DEFAULT
With some ODBC drivers, executing a complex stored procedure may fail with an error similar to: "Cannot open a cursor on a stored procedure that has anything other than a single select statement in it". Using SQL_CUR_USE_ODBC may avoid that error. Also, some drivers don't support the optional row_number parameter in odbc_fetch_row(). SQL_CUR_USE_ODBC might help in that case, too.
I found that using odbc_close($odbchandle) on a connection opened by odbc_pconnect() causes a warning "not a valid ODBC-Link resource". So you can't just change odbc_connect() to odbc_pconnect() and expect things to work without warning messages. However, you can use odbc_close_all() and not get a warning.Ok, learning time. As I was told by the PHP-DevTeam...
Multiple connections are supported, but when you try to connect with exactly the same parameters, an existing
connection will be reused, leading to the behaviour you see.
You can simply omit the calls to odbc_close() since
connections get closed on script termination anyway or better:
Consider making your connection id a global variable or pass
it to your functions.