FOR UPDATE
You are viewing an old version of this article. View
the current version here.
The FOR UPDATE
clause of SELECT applies only when autocommit is set to 0 or the SELECT
is enclosed in a transaction. A lock is acquired on the rows, and other transactions are prevented from writing the rows, acquire locks, and from reading them (unless their isolation level is READ UNCOMMITTED
).
If autocommit
is set to 1, the LOCK IN SHARE MODE and FOR UPDATE
clauses have no effect.
If the isolation level is set to SERIALIZABLE, all plain SELECT
statements are converted to SELECT ... LOCK IN SHARE MODE
.
See Also
Comments
Comments loading...
Content reproduced on this site is the property of its respective owners,
and this content is not reviewed in advance by MariaDB. The views, information and opinions
expressed by this content do not necessarily represent those of MariaDB or any other party.