September 21, 2011 at 5:11 pm
I c your point. The problem is that it's going to be the same change management limitations !
September 21, 2011 at 5:21 pm
And if the query is auto-generated it won't be possible (except maybe with plan guides)
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
September 21, 2011 at 5:28 pm
Ninja's_RGR'us (9/21/2011)
I c your point. The problem is that it's going to be the same change management limitations !
True. It might be an easier sell than getting a maintenance window to re/build indexes, for an interim move.
Re: Change Management, a Plan Guide may be applicable here. Sometimes these can be categorized as "admin work" which have fewer and more flexible change management guidelines...it depends on the shop and how much pain the query is causing.
Edit: heh, Gail beat me to it posting about Plan Guides...these and MAXDOP are just a couple options to consider, to buy some time
There are no special teachers of virtue, because virtue is taught by the whole community.
--Plato
September 23, 2011 at 2:55 am
Great thread.
As its an issue with stats and the optimiser choosing a different plan would adding
OPTION(RECOMPILE)
not help?
We have had similar issues (but not on the same scale i might add!!). I realise you wouldnt be able to add it to the app creating the SQL but just wondered if this would work??
🙂
September 23, 2011 at 3:00 am
Probably not. It's not a case where the plan was compile optimally for one scenario and is performing badly for another (which is when recompile helps). It's that the optimiser is choosing a bad plan during compilation.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
Viewing 5 posts - 31 through 34 (of 34 total)
You must be logged in to reply to this topic. Login to reply