PDO::rollBack
(no version information, might be only in CVS)
PDO::rollBack --
Rolls back a transaction
Description
bool
PDO::rollBack ( void )
Rolls back the current transaction, as initiated by
PDO::beginTransaction(). It is an error to call this
method if no transaction is active.
If the database was set to autocommit mode, this function will restore
autocommit mode after it has rolled back the transaction.
Some databases, including MySQL, automatically issue an implicit
COMMIT when a database definition language (DDL) statement such as
DROP TABLE or CREATE TABLE is issued within a transaction. The implicit
COMMIT will prevent you from rolling back any other changes within the
transaction boundary.
Examples
Example 1. Roll back a transaction
The following example begins a transaction and issues two statements
that modify the database before rolling back the changes. On MySQL,
however, the DROP TABLE statement automatically commits the
transaction so that none of the changes in the transaction are rolled
back.
<?php
/* Begin a transaction, turning off autocommit */
$dbh->beginTransaction();
/* Change the database schema and data */
$sth = $dbh->exec("DROP TABLE fruit");
$sth = $dbh->exec("UPDATE dessert
SET name = 'hamburger'");
/* Recognize mistake and roll back changes */
$dbh->rollBack();
/* Database connection is now back in autocommit mode */
?>
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See Also
| PDO::beginTransaction() |
| PDO::commit() |