There is another interesting SQL Server feature called application locks. This feature allows an application to place the lock to the application resource, which is not related to the database objects and identified by the name only. The lock would follow the regular rules in terms of the lock compatibility, and it can be one of the following types: shared (S), update (U), exclusive (X), intent shared (IS), and intent exclusive (IX).
Note Chapter 17 (Lock Types) describes lock capability matrix.
An application needs ...