HanShi (7/17/2013)
Could you rewrite the delete statement to:
DELETE TOP (20) FROM [dbo].[ServerParametersInstance]WHERE Expiration < @now
This will prevent the query to simultaneously read and delete from the same table.
SQL Server already does this for you. Look at the execution plan, specifically the eager spool.
Having said that, this is an odd little stored procedure. In this article, MS says "If you have to use TOP to delete rows in a meaningful chronological order, you must use TOP together with ORDER BY in a subselect statement." I think MS forgot to put the ORDER BY into the subselect - in which case, your version will achieve the same result with only one read instead of two.
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