Scope of locks when using TRANSACTION ISOLATION LEVEL SERIALIZABLE

Question

The following link describes the serializable transaction isolation level.

http://blogs.msdn.com/b/sqlcat/archive/2011/02/20/concurrency-series-basics-of-transaction-isolation-levels.aspx

Suppose I have one user updating table [dbo].[Table_A]. And another user is updating table [dbo].[Table_B]. And I want to serialize these two update statements (meaning wait for the first to finish before the second one begins), despite the fact that we are touching different tables. I'm guessing I cannot use a table lock, but perhaps a range lock would accomplish this. Can someone help me understand what the code may look like? Or won't this work with transaction isolation level functionality in SQL Server 2008?

Answer 1

You may place application locks:

EXEC  sp_getapplock @resource = 'my_resource_token', @lockMode = 'Exclusive'

UPDATE ...

EXEC  sp_releaseapplock @resource = 'my_resource_token'

This will lock if another session has aquired my_resource_token.