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Performance with index order usage

 
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Vallabhaneni

New User


Joined: 30 Sep 2006
Posts: 4

PostPosted: Thu Mar 05, 2009 2:33 am    Post subject: Performance with index order usage
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Hello,

I need help ond DB2 performance.

I have table T1 index is IX on columns C1, C2, C3, C4 .

right now the sql in the program is

Select * from T1
Where C1 = 1
and C3 = 3
and C4 = 4
and C2 = 2

program is using the index columns in the where clause,

but the index order is C1,C2, C3, C4 but the where cluase is using
C1,C3,C4,C2

Is that matter to performance?.

Please clrify

Thank you
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dick scherrer

Site Director


Joined: 23 Nov 2006
Posts: 19270
Location: Inside the Matrix

PostPosted: Thu Mar 05, 2009 2:38 am    Post subject:
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Hello,

Quote:
Is that matter to performance?.
It should not matter. The optimizer should recognize this.

You might talk with your dba and run an "explain" for confirmation.
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ashimer

Active Member


Joined: 13 Feb 2004
Posts: 551
Location: Bangalore

PostPosted: Thu Mar 05, 2009 4:03 pm    Post subject:
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it doesnt affect performance ....
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