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db2_rollback (no version information, might be only in CVS) db2_rollback --
Rolls back a transaction
Descriptionbool db2_rollback ( resource connection ) | Warning | This function is
EXPERIMENTAL. The behaviour of this function, the
name of this function, and anything else documented about this
function may change without notice in a future release of PHP.
Use this function at your own risk. |
Rolls back an in-progress transaction on the specified connection resource and
begins a new transaction. PHP applications normally default to AUTOCOMMIT
mode, so db2_rollback() normally has no effect unless
AUTOCOMMIT has been turned off for the connection resource.
Note:
If the specified connection resource is a persistent connection, all
transactions in progress for all applications using that persistent
connection will be rolled back. For this reason, persistent connections
are not recommended for use in applications that require transactions.
Return Values
Returns TRUE on success or FALSE on failure.
Examples
Example 1. Rolling back a DELETE statement
In the following example, we count the number of rows in a table, turn
off AUTOCOMMIT mode on a database connection, delete all of the rows in
the table and return the count of 0 to prove that the
rows have been removed. We then issue db2_rollback()
and return the updated count of rows in the table to show that the number
is the same as before we issued the DELETE statement. The return to the
original state of the table demonstrates that the roll back of the
transaction succeeded.
<?php
$conn = db2_connect($database, $user, $password);
if ($conn) {
$stmt = db2_exec($conn, "SELECT count(*) FROM animals");
$res = db2_fetch_array( $stmt );
echo $res[0] . "\n";
// Turn AUTOCOMMIT off
db2_autocommit($conn, DB2_AUTOCOMMIT_OFF);
// Delete all rows from ANIMALS
db2_exec($conn, "DELETE FROM animals");
$stmt = db2_exec($conn, "SELECT count(*) FROM animals");
$res = db2_fetch_array( $stmt );
echo $res[0] . "\n";
// Roll back the DELETE statement
db2_rollback( $conn );
$stmt = db2_exec( $conn, "SELECT count(*) FROM animals" );
$res = db2_fetch_array( $stmt );
echo $res[0] . "\n";
db2_close($conn);
}
?>
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The above example will output: |
Copyright © 1997 - 2007 by the PHP Documentation Group. This material may be distributed only subject to the terms and conditions set forth in the Open Publication License, v1.0 or later. A copy of the Open Publication License is distributed with this manual, the latest version is presently available at http://www.opencontent.org/openpub/.
Please see full copyright text at http://www.php.net/manual/en/copyright.php
Original version of the above documentation is available at http://www.php.net/manual/en/
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