Optimization not enough

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Optimization not enough

Gangadhara MS

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Points: 3377
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April 22, 2014 at 12:11 pm

#290569

Hi,
In my execution plan i can see some warning like:
1. "Type conversion in expression (CONVERT_IMPLICIT(varchar(40),[PAIntel].[ActivationDateTime],0)) may affect "CardinalityEstimate" in query plan choice, Type conversion in expression (CONVERT_IMPLICIT(varchar(24),[Machine].[MachineKey],0)) may affect "CardinalityEstimate" in query plan choice "
2. I am not using any order by clause in my query but still its having an sort with warning as
Operator used tempdb to spill data during execution with spill level 2
3. I have a Key look up (clustred) with high cost how do we remove this.
I am doing join with 2 views (there is no indexed view)
and one table is having 84 million records
Any help much appreciated.
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Gail Shaw SSC Guru Points: 1004504 More actions · Answer 1

Query, table definitions, index definitions please.

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

We walk in the dark places no others will enter
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Gangadhara MS Hall of Fame Points: 3377 More actions · Answer 2

1 st tabel is having 48 Lacks recoprds

the 5 th table is having 84 million records

LutzM SSC Guru Points: 107049 More actions · Answer 3

Wow!

The script name have nothing to identify the table in question.

You really like to provide puzzles, do you?

Also, please provide the code of DML.GetRetailOrOnlineIndicator(), which seems to be a function you're calling in your insert script.

Lutz
A pessimist is an optimist with experience.

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Gangadhara MS Hall of Fame Points: 3377 More actions · Answer 4

CREATE FUNCTION [DML].[GetRetailOrOnlineIndicator](

@GrpID INT

,@ChanID INT

,@SeqNo INT

)

RETURNS NVARCHAR(10)

AS

BEGIN

DECLARE @RetailOrOnlineIndicator NVARCHAR(10)

IF EXISTS (SELECT 1

FROM DML.ExtKeyWestRetailOnlineInfo

WHERE GrpID = @GrpID AND SeqNo = CONVERT( BIGINT, CAST(@ChanID AS VARCHAR(3)) + RIGHT('000000'+ CAST(@SeqNo AS VARCHAR(6)),6) ))

SET @RetailOrOnlineIndicator = 'Online'

ELSE

SET @RetailOrOnlineIndicator = 'Retail'

RETURN @RetailOrOnlineIndicator

END

GO

LutzM SSC Guru Points: 107049 More actions · Answer 5

May I ask for the table definition involved?

You provided a view definition. But we'd need the table def. Especially for [ExtOLSMachine].

Lutz
A pessimist is an optimist with experience.

How to get fast answers to your question[/url]
How to post performance related questions[/url]
Links for Tally Table [/url] , Cross Tabs [/url] and Dynamic Cross Tabs [/url], Delimited Split Function[/url]

Gangadhara MS Hall of Fame Points: 3377 More actions · Answer 6

Gangadhara MS

Hall of Fame

Points: 3377

April 22, 2014 at 2:37 pm

#1707910

i dodn't have any table with name as ExtOLSMachine

LutzM SSC Guru Points: 107049 More actions · Answer 7

The View [DML].[ExtOLSMachineEntitlement] refers to a table DML.ExtOLSMachine.

You might want to take the effort to have a look at your execution plan... -> The table is indeed referenced.

I guess I'm out of this challenge...

Lutz
A pessimist is an optimist with experience.

How to get fast answers to your question[/url]
How to post performance related questions[/url]
Links for Tally Table [/url] , Cross Tabs [/url] and Dynamic Cross Tabs [/url], Delimited Split Function[/url]

Gangadhara MS Hall of Fame Points: 3377 More actions · Answer 8

Hi Can you pls help me to study and understand the execution plan properly, i have not done this work earlier but not sure where to look,what to look so posted all query.

mister.magoo SSC-Forever Points: 47174 More actions · Answer 9

First thing I see in the plan is Query 6 which shows up as 99% of the cost.

Within Query 6, there is a section that accounts for 96% of the plan cost

I suspect (from the estimated and actual rowcounts and the predicates present in the Index Seek on ExtPAIntelActivationEvent.NCIX_ISOCountrycode which includes a condition; ISOCountryCode <> N'' which does not appear anywhere in the query text) that you have another view, perhaps within the Scalar function, perhaps this "DML.ExtKeyWestRetailOnlineInfo"

I would inspect that view to see if it is optimised for the purpose of this query.

I would also rewrite the Scalar function GetRetailOrOnlineIndicator as a Table Valued Function (see here : http://www.sqlservercentral.com/articles/T-SQL/91724/[/url] )

Once that is done, test Query 6 from the plan without the INSERT to see if the row estimates are any better and to see if performance has improved.

MM

select geometry::STGeomFromWKB(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

Optimization not enough

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