need help to simplify this script

Question

Post reply

need help to simplify this script

Viewing 6 posts - 16 through 20 (of 20 total)

You must be logged in to reply to this topic. Login to reply

ramineni.suresh661 Mr or Mrs. 500 Points: 554 More actions · Answer 1

Hey Dwain,

Could you please explain how this query executes to get the count.

Thanks in Advance

Dwain Camps SSC Guru Points: 86948 More actions · Answer 2

Well, I can try. I saw this technique in the "Replace CASE expression and UNPIVOT operator" section of this article: http://beyondrelational.com/modules/2/blogs/70/posts/10905/interesting-enhancements-to-the-values-clause-in-sql-server-2008.aspx

The COUNT(Products) construct is counting non-null values across the columns that are specified in the VALUES set.

I realize that's a pretty brief explanation but I think it conveys the gist of it.

My mantra: No loops! No CURSORs! No RBAR! Hoo-uh![/I]
My thought question: Have you ever been told that your query runs too fast?

My advice:
INDEXing a poor-performing query is like putting sugar on cat food. Yeah, it probably tastes better but are you sure you want to eat it?
The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.

Need to UNPIVOT? Why not CROSS APPLY VALUES instead?[/url]
Since random numbers are too important to be left to chance, let's generate some![/url]
Learn to understand recursive CTEs by example.[/url]
[url url=http://www.sqlservercentral.com/articles/St

ramineni.suresh661 Mr or Mrs. 500 Points: 554 More actions · Answer 3

ramineni.suresh661

Mr or Mrs. 500

Points: 554

June 8, 2012 at 12:53 am

#1498511

Thank you very much

ChrisM@Work SSC Guru Points: 186127 More actions · Answer 4

dwain.c (6/5/2012)
Just to show that I'm keeping current on SQL 2008 stuff, and probably for no other reason, I thought I'd post a less verbose alternative.
SELECT Employee, NEW_LOB, NEW_DEPARTMENT, NEW_COST_CENTRE, NEW_MANAGER, NEW_JOB_CODE, NEW_CYCLE
FROM #Findings
WHERE @NbrProducts >
(SELECT COUNT(Products)
FROM (VALUES (NEW_LOB), (NEW_DEPARTMENT), (NEW_COST_CENTRE)
,(NEW_MANAGER), (NEW_JOB_CODE), (NEW_CYCLE)) t(Products))

Absolutely perfect. Nice job, Dwain.

^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}

For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden

Dwain Camps SSC Guru Points: 86948 More actions · Answer 5

ChrisM@Work (6/8/2012)
dwain.c (6/5/2012)
Just to show that I'm keeping current on SQL 2008 stuff, and probably for no other reason, I thought I'd post a less verbose alternative.
SELECT Employee, NEW_LOB, NEW_DEPARTMENT, NEW_COST_CENTRE, NEW_MANAGER, NEW_JOB_CODE, NEW_CYCLE
FROM #Findings
WHERE @NbrProducts >
(SELECT COUNT(Products)
FROM (VALUES (NEW_LOB), (NEW_DEPARTMENT), (NEW_COST_CENTRE)
,(NEW_MANAGER), (NEW_JOB_CODE), (NEW_CYCLE)) t(Products))
Absolutely perfect. Nice job, Dwain.

Thanks Chris!

I take it you're trolling for low-hanging fruit?

My mantra: No loops! No CURSORs! No RBAR! Hoo-uh![/I]
My thought question: Have you ever been told that your query runs too fast?

My advice:
INDEXing a poor-performing query is like putting sugar on cat food. Yeah, it probably tastes better but are you sure you want to eat it?
The path of least resistance can be a slippery slope. Take care that fixing your fixes of fixes doesn't snowball and end up costing you more than fixing the root cause would have in the first place.

Need to UNPIVOT? Why not CROSS APPLY VALUES instead?[/url]
Since random numbers are too important to be left to chance, let's generate some![/url]
Learn to understand recursive CTEs by example.[/url]
[url url=http://www.sqlservercentral.com/articles/St

ChrisM@Work SSC Guru Points: 186127 More actions · Answer 6

dwain.c (6/8/2012)
ChrisM@Work (6/8/2012)
dwain.c (6/5/2012)
Just to show that I'm keeping current on SQL 2008 stuff, and probably for no other reason, I thought I'd post a less verbose alternative.
SELECT Employee, NEW_LOB, NEW_DEPARTMENT, NEW_COST_CENTRE, NEW_MANAGER, NEW_JOB_CODE, NEW_CYCLE
FROM #Findings
WHERE @NbrProducts >
(SELECT COUNT(Products)
FROM (VALUES (NEW_LOB), (NEW_DEPARTMENT), (NEW_COST_CENTRE)
,(NEW_MANAGER), (NEW_JOB_CODE), (NEW_CYCLE)) t(Products))
Absolutely perfect. Nice job, Dwain.
Thanks Chris!
I take it you're trolling for low-hanging fruit?

Nah mate - wouldn't want to tread on your toes!

^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}

For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden