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How to acquire a table lock for specific time?

Recently one of my colleagues asked me how to acquire an exclusive lock on a database table for a specific amount of time. And this lock should be released once the specified time expires.
You need two components to accomplish this task:
1) Table hints – that puts exclusive lock on the table
2) Delay element – that will hold the lock for a specified amount of time
1) Table hints
Table hint TABLOCKX can be used to acquire exclusive lock on the table.
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SELECT *
FROM <table_name>
WITH (TABLOCKX)
2) Delay element
WAITFOR statement inside transaction block can be used to introduce delay. Following sample code snippet introduces a delay for 10 seconds
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WAITFOR DELAY '00:00:10'
Here is the code snippet that creates a test table, inserts some data and places an exclusive lock for 10 seconds on this table
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CREATE TABLE test_table
  (
     col1 INT
  )
GO
 
INSERT test_table
VALUES (1)
GO
 
DECLARE @delay VARCHAR(8) = '00:00:10'
 
BEGIN TRAN
 
SELECT *
FROM   test_table WITH (TABLOCKX)
WHERE  col1 = '1'
 
WAITFOR DELAY @delay
 
ROLLBACK TRAN
Hope you enjoyed reading this post.


Ref : https://sqlpathy.com/2012/08/22/how-to-acquire-a-table-lock-for-specific-time/

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