Invalidating query cache date dating first teenage tip

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In this case, it is good idea to invalidate whole cache and let hibernate build its cache once again.

You can use below code snippet to invalidate whole hibernate second level cache.

However, these are only considered queries and are only cached to make it easier to find the autoparameterized version of the query if the exact same query with the same constant is reused at a later time.If you run the code below, you will see that none of the queries can reuse the same plan.USE Northwind2; DBCC FREEPROCCACHE; GO SELECT * FROM orders WHERE customer ID = 'HANAR' GO -- Try it again SELECT * FROM orders WHERE customer ID = 'HANAR' GO SELECT * FROM orders WHERE customer ID = 'HANAR'; GO SELECT * FROM Orders WHERE Customer ID = 'HANAR' GO select * from orders where customerid = 'HANAR' GO SELECT usecounts, cacheobjtype, objtype, [text] FROM sys.dm_exec_cached_plans P CROSS APPLY sys.dm_exec_sql_text (plan_handle) WHERE cacheobjtype = 'Compiled Plan' AND [text] NOT LIKE '%dm_exec_cached_plans%'; Note Note that the SELECT statements are all in their own batch, separated by GO.This feature requires no extra work to use, but it is limited to USE Northwind2; DBCC FREEPROCCACHE; GO SELECT * FROM Orders WHERE Customer ID = 'HANAR'; GO SELECT * FROM Orders WHERE Customer ID = 'CHOPS'; GO SELECT * FROM Orders WHERE Customer ID = 'HANAR'; GO SELECT usecounts, cacheobjtype, objtype, [text] FROM sys.dm_exec_cached_plans P CROSS APPLY sys.dm_exec_sql_text (plan_handle) WHERE cacheobjtype = 'Compiled Plan' AND [text] NOT LIKE '%dm_exec_cached_plans%'; You should get two rows back, because the NOT LIKE condition filters out the row for the usecount query itself.The two rows are shown here and indicate that one plan was used only once, and the other was used twice: The results show that with a change of the actual data value, the same plan cannot be reused.

By default, SQL Server is very conservative about deciding when to autoparameterize.

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