I am trying to improve the performance of a query. No matter how bad
it runs the first time, it runs really fast the second time.
So how can I tell if I've done anything to improve the query if it
always comes back quickly after the first run? I assume the
query/data/plan is in cache - how can I clean it out for my session?
Thanks in advance for any help you can provide -
4  13808 
Use" dbcc freeproccache" to clear the proc cache
--
Jack Vamvas
_______________ _______________ _____
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"traceable1 " <tr*****@gmail. com> wrote in message
news:11******** *************@t 31g2000cwb.goog legroups.com...
I am trying to improve the performance of a query. No matter how bad
it runs the first time, it runs really fast the second time.
So how can I tell if I've done anything to improve the query if it
always comes back quickly after the first run? I assume the
query/data/plan is in cache - how can I clean it out for my session?
Thanks in advance for any help you can provide -
Try:
DBCC FREEPROCCACHE
DBCC DROPCLEANBUFFER S
--
Tom
----------------------------------------------------
Thomas A. Moreau, BSc, PhD, MCSE, MCDBA
SQL Server MVP
Toronto, ON Canada
..
"traceable1 " <tr*****@gmail. com> wrote in message
news:11******** *************@t 31g2000cwb.goog legroups.com...
I am trying to improve the performance of a query. No matter how bad
it runs the first time, it runs really fast the second time.
So how can I tell if I've done anything to improve the query if it
always comes back quickly after the first run? I assume the
query/data/plan is in cache - how can I clean it out for my session?
Thanks in advance for any help you can provide -
traceable1 (tr*****@gmail. com) writes: I am trying to improve the performance of a query. No matter how bad
it runs the first time, it runs really fast the second time.
So how can I tell if I've done anything to improve the query if it
always comes back quickly after the first run? I assume the
query/data/plan is in cache - how can I clean it out for my session?
As pointed out by others you can use DBCC FREEPROCCACHE to clear the
plan cache, and DBCC DROP CLEANBUFFERS to clean the data cache. But
don't do this on a production machine, as it affects the entire server.
Another reason you get better performance the second time, could be that
SQL Server has auto-statistics and improved statistics gives you a
better query plan.
--
Erland Sommarskog, SQL Server MVP, es****@sommarsk og.se
Books Online for SQL Server 2005 at http://www.microsoft.com/technet/pro...ads/books.mspx
Books Online for SQL Server 2000 at http://www.microsoft.com/sql/prodinf...ons/books.mspx
That did it! Thank you very much!!!
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