Closes an Oracle connection

# oci_close

(PHP 5, PHP 7, PHP 8, PECL OCI8 >= 1.1.0)

oci_close — Closes an Oracle connection

### Description

oci_close(resource `$connection`): ?bool

Unsets `connection`. The underlying database connection is closed if no other resources are using it and if it was created with oci_connect() or oci_new_connect().

It is recommended to close connections that are no longer needed because this makes database resources available for other users.

### Parameters

`connection`

  An Oracle connection identifier returned by oci_connect(), oci_pconnect(), or oci_new_connect().

### Return Values

Returns `null` when oci8.old_oci_close_semantics is enabled, or `true` otherwise.

### Examples

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 longer 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"
?>`

### Notes

> 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:

> The oci_close() function does not close the underlying database connections created with oci_pconnect().

### See Also

- oci_connect() - Connect to an Oracle database
- oci_free_statement() - Frees all resources associated with statement or cursor

`↑` and `↓` to navigate • `Enter` to select • `Esc` to close • `/` to open