oci_close
(PHP 5, PHP 7, PECL OCI8 >= 1.1.0)
oci_close — 关闭 Oracle 连接
说明
$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。
