My understanding of the WITH RECOMPILE
option with stored procedures is generally limited to using the clause with a single stored proc call as a trailing parameter:
exec sp_mystoredproc 'Parameter1', 2, '1/28/2011' with recompile
What are the effects of including WITH RECOMPILE
in the actual proc definition? Does this recompile the proc every time it's executed? Or just the next time the proc is altered?
Example:
CREATE PROCEDURE [dbo].[sp_mystoredproc]
(@string1 varchar(8000)
,@int2 int = 2
,@dt_begin DATETIME
with recompile
AS
... proc code ...
To recompile a stored procedure by using sp_recompile This does not execute the procedure but it does mark the procedure to be recompiled so that its query plan is updated the next time that the procedure is executed.
Remarks. sp_recompile looks for an object in the current database only. The queries used by stored procedures, or triggers, and user-defined functions are optimized only when they are compiled.
Stored Procedure is nothing but a precompiled SQL statement. This means that once we compile a query, it stores the result and the next time we don't need to compile it again and again. It means it is prepared SQL code that you can save and reuse later multiple times.
What is the RECOMPILE option? The compilation is the process when a query execution plan of a stored procedure is optimized based on the current database objects state. This query execution plan is often stored in the cache to be quickly accessed. Recompilation is the same process as a compilation, just executed again.
This makes the proc rebuild the plans of all queries every time it's run.
Useful it the values of the proc parameters affect the filter selectivity.
Say, the optimal plan for this query:
SELECT *
FROM orders
WHERE order_date BETWEEN @begin_report AND @from_report
will be a full scan if the date range is large or an index scan if it's small.
Created using WITH RECOMPILE
, the proc will build the plan on each execution; without one, it will stick to a single plan (but will save time on recompilation itself).
This hint is usually used in procs processing large volumes of data and doing complex reports, when the overall query time is large and time for rebuilding the plan is negligible compared with the time saved by a better plan.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With