How do I rollback a MySQL query?
You will need set AUTOCOMMIT=0 , and after you can issue COMMIT or ROLLBACK at the end of query or session to submit or cancel a transaction. You can only do so during a transaction. Basically: If you’re doing a transaction just do a rollback. Otherwise, you can’t “undo” a MySQL query.
Is rollback possible in MySQL?
MySQL Transaction cannot be able to roll back all statements. For example, these statements include DDL (Data Definition Language) commands such as CREATE, ALTER, or DROP database as well as CREATE, UPDATE, or DROP tables or stored routines.
What is ROLLBACK and COMMIT?
A COMMIT statement is used to save the changes on the current transaction is permanent. A Rollback statement is used to undo all the changes made on the current transaction. If all the statements are executed successfully without any error, the COMMIT statement will permanently save the state.
How to roll back a transaction in MySQL?
To roll back the current transaction and cancel its changes, you use the ROLLBACK statement. To disable or enable the auto-commit mode for the current transaction, you use the SET autocommit statement. By default, MySQL automatically commits the changes permanently to the database.
What happens when a SQL statement rolls back?
If a single SQL statement within a transaction rolls back as a result of an error, such as a duplicate key error, locks set by the statement are preserved while the transaction remains active. This happens because InnoDB stores row locks in a format such that it cannot know afterward which lock was set by which statement.
What is the read only restriction in MySQL 5.6?
The READ ONLY restriction prevents the transaction from modifying or locking both transactional and nontransactional tables that are visible to other transactions; the transaction can still modify or lock temporary tables. These modifiers are available as of MySQL 5.6.5.
What is the start transaction in MySQL 5.6?
START TRANSACTION permits several modifiers that control transaction characteristics. To specify multiple modifiers, separate them by commas. The WITH CONSISTENT SNAPSHOT modifier starts a consistent read for storage engines that are capable of it. This applies only to InnoDB.