Viewing 15 posts - 46,696 through 46,710 (of 49,552 total)
The optimiser's very good usually. This is just an edge case where its estimate is wrong. Possibly because the table's a heap, not a cluster.
If you don't have a clustered...
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
May 5, 2008 at 2:20 pm
I can't remember offhand. I did read it somewhere.
I think it's around 100 pages, but don't quote me on that. I'll see if I can find the source article tomorrow.
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
May 5, 2008 at 2:16 pm
Depends how much usage your tempDB gets. How big is the file set for now?
For the proportional fill to work, all the files should be the same size, so autogrow...
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
May 5, 2008 at 1:21 pm
Good point. What kind of data is in this database?
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
May 5, 2008 at 1:17 pm
What error do you get when you try to drop it?
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
May 5, 2008 at 1:00 pm
Because fragmentation has very little meaning on such small tables. Logical fragmentation is defined as the number of out of order pages. With only 1 page in the table it's...
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
May 5, 2008 at 12:59 pm
Ok.
My guess. As far as the optimiser's concerned, the query returns too many rows for a seek/bookmark lookup to be optimal, and the index is not covering. Hence it uses...
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
May 5, 2008 at 12:57 pm
Q (5/5/2008)
• Create many files to maximize disk bandwidth and to reduce contention in allocation structures. As a general guideline, create one data file per CPU. Each file...
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
May 5, 2008 at 12:49 pm
The consider yourself lucky you still have a database.
If you want recommendations for your boss -
Change the web user to have the minimum required privileges
Go through...
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
May 5, 2008 at 12:47 pm
Google 'SQL injection' then fix the web front end so that it checks input and uses parameters properly.
Forget delete statement. What if it had been a drop table or drop...
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
May 5, 2008 at 12:37 pm
Can you post table schema, index definition, query and aprox rowcount affected by the query please?
It's probably because the index is not covering, and query affects enough rows that the...
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
May 5, 2008 at 12:35 pm
You need some column that defines which status is first for each code.
You cannot depend on the order that the rows are returned as that will change.
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
May 5, 2008 at 8:19 am
Pleasure. I don't bother bookmarking all the white papers, just use this rather.
http://www.sqlskills.com/whitepapers.asp
I don't know offhand of the article on why 1 file/cpu. Perhaps on the PSS engineer's blog? http://blogs.msdn.com/psssql
Soem...
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
May 5, 2008 at 8:15 am
SQL King (5/5/2008)
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
May 5, 2008 at 8:07 am
SQL King (5/5/2008)
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
May 5, 2008 at 8:06 am
Viewing 15 posts - 46,696 through 46,710 (of 49,552 total)