Viewing 15 posts - 14,476 through 14,490 (of 49,552 total)
It repairs the database, nothing more. Go read up on it in Books Online (clearly documented)
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
February 2, 2013 at 1:33 am
Join hints are a bad idea in most cases. Rather see why SQL's picking a loop join (probably low row estimations on one or both tables) and fix the cause.
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
February 1, 2013 at 3:04 pm
jfogel (2/1/2013)
One last question. I read that when executing the enable RCS command that there can't be any other connections or transactions open in that database.
Correct
Then the article goes on...
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
February 1, 2013 at 3:03 pm
sqlfriends (2/1/2013)
If target server memory is much less than total server memory, is it under memory pressure?
Not SQL, but likely the OS. Target lower than total means SQL's been told...
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
February 1, 2013 at 12:49 pm
Just increased TempDB usage. The snapshot isolation levels use row versioning instead of locks, and those row versions go into TempDB. Long-running transactions will result in the versions not getting...
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
February 1, 2013 at 12:46 pm
Without knowing the underlying indexes, not really. It's not the syntax, the optimiser's smart enough to convert the forms, it's going to be the indexes that make a difference.
Without knowing...
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
February 1, 2013 at 12:38 pm
Because the optimiser works on the entire query in one go, not the subquery first and the outer query second, the two very likely simplify to the same form.
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
February 1, 2013 at 12:05 pm
No way to tell without seeing the indexes and exec plan. Probably the indexes don't support the additional predicates, possibly combined with row estimation errors (NOT is a little hard...
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
February 1, 2013 at 11:55 am
If you're already seeing lock escalation, disabling page locks will likely make that escalation worse.
With page locks allowed, SQL can take locks at row, page or table. If it find...
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
February 1, 2013 at 11:53 am
Is there a question here?
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
February 1, 2013 at 11:44 am
Either the stats got sufficiently out of date (see referenced blog post) or the data volume increase and passed a tipping point where the plan changed dramatically
There's definitely some room...
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
February 1, 2013 at 11:43 am
Tried breaking it up? Insert the tvf into a temp table, join the temp table.
Can't tell much about the row count, the plans are estimated, but SQL thinks it's dealing...
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
February 1, 2013 at 10:31 am
btw, you do know what nolock does?
See - http://blogs.msdn.com/b/davidlean/archive/2009/04/06/sql-server-nolock-hint-other-poor-ideas.aspx
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
February 1, 2013 at 10:24 am
Master, model, msdb and resource, leave them alone, unless you have a really good reason to change them (and even then, just model and maybe msdb).
TempDB:
http://support.microsoft.com/kb/917047
http://technet.microsoft.com/library/Cc966545
http://www.sqlskills.com/blogs/paul/category/tempdb/
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
February 1, 2013 at 10:21 am
asmita.patel (2/1/2013)
for example
select a.*
from <<tbl_aa>> a with (nolock)
Join <<tbl_bb>> b with (nolock) on a.aa_id = b.bb_id
--Note: You need to...
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
February 1, 2013 at 8:50 am
Viewing 15 posts - 14,476 through 14,490 (of 49,552 total)