oci_close()
(PHP 5, PHP 7, PECL OCI8 >= 1.1.0)
关闭 Oracle 连接
说明
oci_close(resource $connection): bool
oci_close()将 Oracle 连接$connection关闭。
Note:自版本 1.1 起oci_close()正确关闭 Oracle 连接。使用oci8.old_oci_close_semantics选项来恢复本函数的旧行为。
成功时返回TRUE
,或者在失败时返回FALSE
。
Note:在 PHP 5.0.0 之前的版本必须使用ocilogoff()替代本函数。该函数名仍然可用,为向下兼容作为oci_close()的别名。不过其已被废弃,不推荐使用。
参数
- $connection
An Oracle connection identifier returned by oci_connect(),oci_pconnect(), or oci_new_connect().
返回值
成功时返回TRUE
,或者在失败时返回FALSE
。
范例
Example #1 Closing a connection
Resources associated with a connection should be closed to ensure the underlying database connection is properly terminated and the database resources are released.
<?php $conn = oci_connect('hr', 'welcome', 'localhost/XE'); if (!$conn) { $e = oci_error(); trigger_error(htmlentities($e['message'], ENT_QUOTES), E_USER_ERROR); } $stid = oci_parse($conn, 'SELECT * FROM departments'); $r = oci_execute($stid); oci_fetch_all($stid, $res); var_dump($res); // Free the statement identifier when closing the connection oci_free_statement($stid); oci_close($conn); ?>
Example #2 Database connections are not closed until all references are closed
The internal refcount of a connection identifier must be zero before the underlying connection to the database is closed.
<?php $conn = oci_connect('hr', 'welcome', 'localhost/XE'); if (!$conn) { $e = oci_error(); trigger_error(htmlentities($e['message'], ENT_QUOTES), E_USER_ERROR); } $stid = oci_parse($conn, 'SELECT * FROM departments'); // this increases the refcount on $conn oci_execute($stid); oci_fetch_all($stid, $res); var_dump($res); oci_close($conn); // $conn is no long usable in the script but the underlying database // connection is still held open until $stid is freed. var_dump($conn); // prints NULL // While PHP sleeps, querying the Oracle V$SESSION view in a // terminal window will show that the database user is still connected. sleep(10); // When $stid is freed, the database connection is physically closed oci_free_statement($stid); // While PHP sleeps, querying the Oracle V$SESSION view in a // terminal window will show that the database user has disconnected. sleep(10); ?>
Example #3 Closing a connection opened more than once
When database credentials are reused, both connections must be closed before the underlying database connection is closed.
<?php $conn1 = oci_connect('hr', 'welcome', 'localhost/XE'); // Using the same credentials reuses the same underlying database connection // Any uncommitted changes done on $conn1 will be visible in $conn2 $conn2 = oci_connect('hr', 'welcome', 'localhost/XE'); // While PHP sleeps, querying the Oracle V$SESSION view in a // terminal window will show that only one database user is connected. sleep(10); oci_close($conn1); // doesn't close the underlying database connection var_dump($conn1); // prints NULL because the variable $conn1 is no longer usable var_dump($conn2); // displays that $conn2 is still a valid connection resource ?>
Example #4 Connections are closed when variables go out of scope
When all variables referencing a connection go out of scope and are freed by PHP, a rollback occurs(if necessary)and the underlying connection to the database is closed.
<?php function myfunc() { $conn = oci_connect('hr', 'hrpwd', 'localhost/XE'); if (!$conn) { $e = oci_error(); trigger_error(htmlentities($e['message'], ENT_QUOTES), E_USER_ERROR); } $stid = oci_parse($conn, 'UPDATE mytab SET id = 100'); oci_execute($stid, OCI_NO_AUTO_COMMIT); return "Finished"; } $r = myfunc(); // At this point a rollback occurred and the underlying database connection was released. print $r; // displays the function return value "Finished" ?>
注释
Note:Variables that have a dependency on the connection identifier, such as statement identifiers returned by oci_parse(), must also be freed before the underlying database connection is closed.
Note:Prior to version PHP 5.1.2(PECL OCI8 1.1)oci_close() was a no-op. In more recent versions it correctly closes the Oracle connection. Use oci8.old_oci_close_semantics option to restore old behavior of this function.
Note:The oci_close() function does not close the underlying database connections created with oci_pconnect().
Note:In PHP versions before 5.0.0 you must use ocilogoff() instead.在当前版本中,旧的函数名还可以被使用,但已经被废弃并不建议使用。
参见
oci_connect()
建立一个到 Oracle 服务器的连接oci_free_statement()
释放关联于语句或游标的所有资源
please note, you can use oci_close() to close persistent connections opened with oci_pconnect() in PHP ver 5.3 or above. as stated in here: http://www.php.net/manual/en/oci8.configuration.php#ini.oci8.persistent-timeout
For using persistent connections && being able to sleep, I use: function close_db_locks_on_abort( ) { global $conn; if( connection_aborted() ) { $fp = fopen( "/tmp/shutdown-func.txt", "a" ); fwrite( $fp, sprintf( "connection aborted on %s\n", date( "d-m-Y H:i:s" ) ) ); if( $conn ) { OCIRollBack( $conn ); fwrite( $fp, sprintf( "-- DURING CONNECTION! ip=%s, user=%s, page=%s\n", $_SERVER["REMOTE_ADDR"], $_SERVER["PHP_AUTH_USER"], $_SERVER["SCRIPT_FILENAME"] ) ); } fclose( $fp ); } } register_shutdown_function ( "close_db_locks_on_abort" ); This makes sure a rollback is done on a connection when a user hits 'stop', so there will be no locks on table rows.