It instructs Adaptive Server not to save a.
OPTION RECOMPILE SQL SERIES
This post summarizes the entire series of parameter sniffing, performance and. The first is the OPTION (RECOMPILE) hint, which can be applied to.
Performance and Recompiling Query Summary. There are three ways to tell SQL Server to recompile every execution of a query. After that, as a part of the query execution process, the query plan is generated and stored in. 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. First it parses and normalizes the SQL Server statements then it compiles and optimizes the statements. We talked briefly about implementing a plan guide, which is certainly not simpler, but then a colleague suggested that you could fool the optimizer by "hiding" the parameterized statement inside a stored procedure, view, or inline table-valued function. In the create procedure statement, the optional clause with recompile comes immediately before the SQL statements. At a high level, the query processor goes through multiple phases before producing a query plan in SQL Server.
OPTION RECOMPILE SQL CODE
If you changed the variable to = 1, then you get the more expensive clustered index scan you should expect:īut nobody likes using dynamic SQL in an edge case like this - it makes code harder to read and maintain, and even if this code were out in the application, it's still additional logic that would have to be added there, making it less than desirable. This leads to the same efficient plan as above. DECLARE bit = 0 DECLARE nvarchar ( max ) = N'SELECT dynsql = OrderID, OrderDate FROM dbo.Orders' + CASE WHEN IS NOT NULL THEN N' WHERE IsShipped = ELSE N'' END + CASE WHEN = 0 THEN N' OPTION (RECOMPILE)' ELSE N'' END EXEC sys. The main reason why Microsoft introduced table variable in SQL Server 2000 is to reduce stored procedure recompilations (a recompilation occurs when the.
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