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index only accsess?

 
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mailsaurabh.tripathi

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Joined: 22 May 2008
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PostPosted: Fri Oct 23, 2009 7:48 pm    Post subject: index only accsess?
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Can someone provide me info on how does DB2 perform index only access?
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dick scherrer

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PostPosted: Fri Oct 23, 2009 9:06 pm    Post subject:
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Hello,

By only accessing the index?

Your question is not clear. . . icon_confused.gif

What are trying to learn?
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Steve Davies

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PostPosted: Fri Oct 23, 2009 9:38 pm    Post subject:
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If all the columns you want to retrieve are in the index, then it can meet your select statement criteia by only going to the index, therefore it does not need to go to the tablespace to get any extra columns. This is an index only access. It is more efficient for obvious reasons.
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