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DB2 Index scan and sequential scan

 
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mosinjamadar

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Joined: 26 Sep 2007
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Location: pune

PostPosted: Mon Feb 11, 2008 11:33 am    Post subject: DB2 Index scan and sequential scan
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Hi

If I have defined INDEX on COLUMN1 COLUMN2 COLUMN3 and in SELECT
query in WHERE clause i will specify only COLUMN1 COLUMN2 still DB2 does INDEX scan or it will be sequential scan
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acevedo

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PostPosted: Mon Feb 11, 2008 12:43 pm    Post subject:
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maybe column1 and column2 are not good candidates for index or try runstats.
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dbzTHEdinosauer

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PostPosted: Mon Feb 11, 2008 3:13 pm    Post subject:
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Quote:

sequential scan

do you mean table scan?
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acevedo

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PostPosted: Mon Feb 11, 2008 4:28 pm    Post subject:
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now that I've read again the post:

DB2 should choose Index Access with Matchcols=2.
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