![]() This can improve the procedure's processing performance. If a database undergoes significant changes to its data or structure, recompiling a procedure updates and optimizes the procedure's query plan for those changes. When a procedure is compiled for the first time or recompiled, the procedure's query plan is optimized for the current state of the database and its objects. It also describes using the sp_recompile system stored procedure to recompile an existing procedure. This topic describes using the WITH RECOMPILE option when creating a procedure definition and executing an existing procedure. There are three ways to do this: WITH RECOMPILE option in the procedure definition or when the procedure is called, the RECOMPILE query hint on individual statements, or by using the sp_recompile system stored procedure. ![]() This topic describes how to recompile a stored procedure in by using. Since I have introduced this measure to my procedures, I’m not surprised anymore with waits or “hanging” queries.>=aps-pdw-2016||=azuresqldb-current||=azure-sqldw-latest||>=sql-server-2016||>=sql-server-linux-2017||=azuresqldb-mi-current It is just nicer to still have some control than using the club-like option WITH RECOMPILE on stored procedure level. In that way, we are still able to analyze the stats afterwards – if you ever want to. RECOMPILE Query CREATE PROCEDURE Īs you can see, each statement has its own OPTION(RECOMPILE). No way to sniff what SQL Server has actually done when the procedure did run. WITH RECOMPILE on stored procedure level is a very drastic measure. So, what options do we have: RECOMPILE Stored Procedure CREATE PROCEDURE I’m willing to wait a second to get a decent execution plan. But I don’t need to update my objects every minute. Totally agreed.īut in BI we have little bit more time. If you have tons of transactions and need every time to RECOMPILE, it is a waste of time. What they don’t mention is, that they are writing those queries for OLTP application. Instead improve your query writing skills and build better indexes and so on. If you google for information about it, there are plenty of voices who suggest, to not use it. And this can lead to longer running queries or even “hanging” queries. ![]() It takes the assumption of the previous run and applies it to the small delta load. On the following loads, it sees the data and the already existing execution plan and thinks, okay, we have a plan, so let’s get it done. Well, THIS execution plan would be the best to process THAT lot of data. So, SQL Server sees all the data and thinks, wow, a lot to process. Usually in my business vault satellites, the first load will be the biggest. If tables are around, it gets the counts and other meta-data and tries to figure out the best way to process. When I compile now the stored procedure, SQL Server tries to already create an execution plan which is saved with the stored procedure. hashes and filter after that the needed 100000 or vice-versa. The temporary table is needed, because sometimes SQL Server doesn’t know if it should calculate 100 Mio. My typical layout looks like this: CREATE PROCEDURE In BI I work with data sets.Īs you have discovered, my loading functions are all created with Stored Procedures. No OLTP optimization or single record stuff. I would like to discuss and explain certain behaviors I discovered in BI and BI only. I’m far from being an expert in that field. Reading and optimizing execution plans is a huge playing field. It will tell the SQL engine how it should optimize the execution plans. You rewrite parts of the query, try to ease the pain of the SQL engine.Īnd some when you come across OPTIONs, which can be added to your table, your joins, your query or your stored procedure. And suddenly it appears, as if your queries are stuck. The more you learn, the more you are going to use. With time your skills evolve, and you learn how to optimize the queries, maybe using a temporary table or a common table expression. At the beginning as an analyst you are going to learn to write standard SQL queries to get your desired results.
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