![]() ![]() Summary of the downsidesĮach statement with option recompile consumes extra cpu and memory and doesn’t store the execution plan in cache, preventing performance tuners from seeing metrics like total execution count, or total worker time in dm_exec_query_stats. SET STATISTICS TIME ON Įvery time that statement runs, it will be compiled again, costing those 5 ms of CPU time. JOIN Users as U2 on Posts.LastEditorUserId = U2.Id JOIN Users as U on Posts.OwnerUserId = U.Id To see the cost of compilation, just use statistics time. Okay, but what about the cost of compilation? When a stored procedure, prepared queries and queries submitted via spexecutesql. ![]() To prove that, I’ll right-click on the top SELECT INTO and view the properties. Posted by Karthick P.K on October 8, 2012. exec 4Įach “query” in this example is a separate statement. Then, I’ll get the actual execution plan for post type 4. I’ll run the stored procedure with the value of 3, first. This stored procedure has OPTION(RECOMPILE) on only one statement INT) asįROM Posts where PostTypeId = PostTypeId, Tags, Body Except for this example, I can’t use the estimated execution plan because there’s a temp table. I’m going to re-use the stored procedure from this post on parameter sniffing and using the estimated execution plan. There’s also the fact that the hint applies strictly to the statement level, not the entire query. Using option recompile will use extra cpu and memory every time the statement compiles. I have a few reasons why this hint is dangerous. In fact, the statement with option recompile won’t be stored in cach e. SQL SERVER Parameter Sniffing and OPTION (RECOMPILE) The oldest and most traditional technique to not cache the query plans and compile your stored procedure or queries every single time to get optimal performance. It also means that the statement itself won’t be vulnerable to parameter sniffing from other queries in cache. This new database level enhancement was introduced recently which can help you overcome any issue with the parameter sniffing. ![]() You will see an SP:Recompile event with event subclass 1 (Schema. sprecompile accomplishes recompilations by incrementing the on-disk schema version of the object in question. There’s some benefits, like something called “ constant folding.” To us, that just means that the execution plan might be better than a normal execution plan compiled for the current statement. When sprecompile is run on a table or a view, all of the stored procs/triggers/UDFs that reference that table or view will be recompiled the next time they are run. SQL Server will compile an execution plan specifically for the statement that the query hint is on. What happens when a statement has OPTION(RECOMPILE) Put the OPTION (RECOMPILE) on the query that is using the function. spBlitz Free SQL Server Health Check Script Stored Procedure Created WITH RECOMPILE Option spBlitz Result: Stored Procedure WITH RECOMPILE Option When you create a stored procedure using the WITH RECOMPILE option, it gets a brand new execution plan every time it runs. I’ve used it before without fully understanding the impact. 1 Answer Sorted by: 12 Inline Table Valued Functions are expanded out into the calling query so nothing is ever actually called. I wish I knew that when I started query tuning. ![]()
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