Viewing 15 posts - 20,356 through 20,370 (of 22,219 total)
Yeah. I'm actually working on comparing MAX, TOP and ROW_NUMBER. I was hoping to outline which might be better when.
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
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May 21, 2008 at 1:18 pm
Ah, partition by... crud. I was bouncing all around it and I just couldn't figure it out. That looks great. I tested it against the single row and large set...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
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May 21, 2008 at 12:44 pm
You'll need to look at the queries being run and determine what the most likely access paths are for your data. There you'll want to put indexes. After that initial...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
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May 21, 2008 at 9:58 am
Since backups are just from committed transactions, I doubt you can move the log in that manner. Can't the Log Explorer read from log backups directly? I'm pretty sure the...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
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May 21, 2008 at 9:01 am
Itzik was doing it on demand. It wasn't hard either. He just had to get the queries to run against similar sets of data and he could force the issue...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
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SQL Server Query Performance Tuning
May 21, 2008 at 8:45 am
Actually, according to Itzik Ben Gan and some pretty convincing tests (he gave the presentation at the last PASS Summit), NOLOCK can result in duplicate and incorrect data because it...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning
May 21, 2008 at 7:33 am
The short answer is, it depends. The longer answer is, that in some cases, yes, it makes a huge difference to put the filters into the JOIN instead of the...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning
May 21, 2008 at 6:38 am
Check the execution plan. I'll be you're seeing tons of table or index scans.
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning
May 21, 2008 at 6:23 am
You can't join outside the OUTPUT clause, but since you've put the records into a table variable (you might want to use a temp table for this instead) you can...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
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May 21, 2008 at 6:18 am
Just to be a bit contrarian, I agree with Jeff & Gail on TableA, but on Table B, I'd look at making the foreign key value from TableA the leading...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning
May 21, 2008 at 6:13 am
Have you looked at the execution plan? You need to identify where the bottlenecks are occuring in order to know where to go to work. The others have pointed out...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
SQL Server Query Performance Tuning
May 21, 2008 at 6:09 am
I'm working up a comparison between TOP, MAX and ROW_NUMBER that addresses this problem. You can use all three. They have different strengths and weaknesses. You can use them as...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
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May 21, 2008 at 5:52 am
I'm working from home today so I don't have all my reference material at hand. If I miss a detail here & there, someone will correct me.
Select statements put a...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
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May 21, 2008 at 4:50 am
Sorry, I guess I wasn't clear, you don't need an UPDLOCK on the UPDATE because that's what it does. For example, and this is a bit contrived, you need to...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
SQL Server Execution Plans
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May 20, 2008 at 12:30 pm
A select creates shared locks on the table. If you want to limit access as part of a single transaction, a good idea, you need to put a UPDLOCK hint...
"The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood"
- Theodore Roosevelt
Author of:
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SQL Server Query Performance Tuning
May 20, 2008 at 10:55 am
Viewing 15 posts - 20,356 through 20,370 (of 22,219 total)