(Quick Reference)
lock
Purpose
The
lock method obtains a pessimistic lock using an SQL
select … for update.
Examples
def book = Book.get(1)
book.lock()
Description
The
lock method will obtain a pessimistic lock on an instance, essentially locking a row in the database with
select … for update. The
lock method is equivalent to using Hibernate's
LockMode.UPGRADE in combination with the
lock method.
The lock will automatically be released when the transaction is committed. In Grails this is typically after an action has finished executing.
Refer to the section on
Optimistic and Pessimistic locking in the user guide for info.
