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mailsaurabh.tripathi

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Joined: 22 May 2008
Posts: 56
Location: hyderabad

PostPosted: Mon Aug 23, 2010 5:29 pm    Post subject: Suitable Index
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Hi

If an index is having a low first key cardf, relatively small as compared to the full cardf, then how good is that index?
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mailsaurabh.tripathi

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Joined: 22 May 2008
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Location: hyderabad

PostPosted: Mon Aug 23, 2010 5:33 pm    Post subject: column details for last question
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Col Name Null Type Colcard
1 PROMO Y INTEGER 11063
2 DETAIL_ID N INTEGER 22528
3 DETL_TYP N SMALLINT 5
4 IM_ID N DECIMAL(14,0) 36864
5 LOCATION N SMALLINT 1
6 ZONE N INTEGER 759
7 AREA N CHAR(3) 51
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GuyC

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PostPosted: Mon Aug 23, 2010 5:48 pm    Post subject:
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It depends :
How many matching Cols is that index (mostly) used
Is the index used in Sort Avoidance
Is the index used for R.I. checking

A low firstkeycardf says very little about the "quality" of an index.
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