Jeff Moden

Forum Replies Created

Viewing 15 posts - 43,771 through 43,785 (of 59,101 total)

RE: Eliminating Cursors

Praveen,
What version of SQL Server are you using? 2k, 2k5, 2k8?
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 15, 2009 at 4:50 pm

#995755
RE: "tempdb" size -- 550GB!

Robert (5/15/2009)
See if there is any kind of sort in execution plan. Cross join can produce a huge result, but not necessarily anything in tempdb.
If you have an "order...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 15, 2009 at 8:17 am

#995370
RE: "tempdb" size -- 550GB!

Attila (5/15/2009)
I'd recommend to run a trace, and look for autogrow events.
Paralelly start a script which runs in every minutes, and writs out the inputbuffer of each spid>49, plus the...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 15, 2009 at 8:14 am

#995364
RE: Is a Temporary Table Really Necessary?

alex (5/15/2009)
> I am not fond of cursors and advocate doing anything possible to replace the cursor
What do you gain by handling the looping yourself rather than just using a...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 15, 2009 at 8:12 am

#995362
RE: The "Numbers" or "Tally" Table: What it is and how it replaces a loop.

I found the code I used to gen a Tally table on the fly using what Oracle calls "Subquery Refactoring" which is a fancy name for "CTE". Add a...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 9:44 pm

#995037
RE: Checksum value for finding changed data advice

Haven't need to try it. I'm pretty fortunate in that most of the data providers I "meat" up with respond pretty well at the mere threat of a malstrome...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 8:23 pm

#995018
RE: "tempdb" size -- 550GB!

Barkingdog (5/9/2009)
Jeff,
Per the Extimated Execution Plan, TableA (with 60 millon rows) uses about 56% of the query for a table scan! (I will investigate the "predicate" shown in the...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 8:05 pm

#995012
RE: Checksum value for finding changed data advice

Got it and mostly agree especially since CHECKSUM is not a guarantee that something has changed or not.
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 7:58 pm

#995009
RE: Checksum value for finding changed data advice

Bruce W Cassidy (5/14/2009)
Jeff Moden (5/14/2009)
The performance on a persisted calculated column is "sucky"?
[font="Verdana"]Yup. You persist it by creating an index over it, right? So when you do...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 7:43 pm

#995003
RE: Queries running slower in SQL 2008 than in SQL 2000

christophe.mulotti (5/14/2009)
The query on witch i'm struggling is the following :
SELECT DISTINCT Cast(Cast(Col1 as nVarchar(2))+Cast(col2 as nVarchar(3))) as nvarchar(5)) as invalidValue
FROM Table1
WHERE Cast(Cast(Col1 as nVarchar(2))+Cast(col2 as nVarchar(3))) as nvarchar(5))...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 7:28 pm

#995001
RE: Checksum value for finding changed data advice

Bruce W Cassidy (5/14/2009)
[font="Verdana"]A persisted value can help. However, from experience... don't bother -- the performance is too sucky.
The performance on a persisted calculated column is "sucky"?
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 7:14 pm

#994998
RE: Which is the best way?

Is it homework, a test, of a job interview? ALL of that information is in Books Online. I recommend you spend a bit of time there. Hope...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 11:29 am

#994752
RE: Simple query yet difficult

usman.tanveer (5/14/2009)
Christopher Stobbs (5/14/2009)
DECLARE @MyTable TABLE (Id INT, Team CHAR(1)) INSERT INTO @MyTable SELECT 1, 'A' UNION ALL SELECT 2, 'A' UNION ALL SELECT 3, 'A' UNION ALL SELECT 3, 'B' SELECT Id,MAX(Team) FROM @MyTable GROUP BY Id
Thanks for...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 11:19 am

#994740
RE: Checksum value for finding changed data advice

Shawn Therrien (5/14/2009)
I'm using SSIS (but you could use this in straight TSQL) to compare fields from two rows of data - say on a basic Person Table, just Firstname,...
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 11:12 am

#994734
RE: Are the posted questions getting worse?

Steve Jones - Editor (5/13/2009)
Ahhh, Klingons asking questions. About databases? Could be interesting....
Heh... still not as bad as some of the questions folks ask on the forums. 😀
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)

May 14, 2009 at 10:49 am

#994708

Viewing 15 posts - 43,771 through 43,785 (of 59,101 total)