PDO::rollBack
(PHP 5 >= 5.1.0, PHP 7, PHP 8, PECL pdo >= 0.1.0)
PDO::rollBack — Rolls back a transaction
Beschreibung
Rolls back the current transaction, as initiated by PDO::beginTransaction().
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.
Parameter-Liste
Diese Funktion besitzt keine Parameter.
Rückgabewerte
Gibt bei Erfolg true
zurück. Bei einem Fehler wird false
zurückgegeben.
Fehler/Exceptions
Throws a PDOException if there is no active transaction.
Hinweis: Eine Exception wird auch dann ausgelöst, wenn das Attribut
PDO::ATTR_ERRMODE
nichtPDO::ERRMODE_EXCEPTION
ist.
Beispiele
Beispiel #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 */
?>
Siehe auch
- PDO::beginTransaction() - Initiates a transaction
- PDO::commit() - Commits a transaction
- Transactions and auto-commit