Re: way to speed up a SELECT DISTINCT?

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От Christopher Kings-Lynne
Тема Re: way to speed up a SELECT DISTINCT?
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Msg-id 20031010190403.E61002-100000@houston.familyhealth.com.au
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Ответ на Re: way to speed up a SELECT DISTINCT?  (Seth Ladd <seth@picklematrix.net>)
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> Thanks for the tip, I'll give this a shot soon.  I am curious, your
> example above does not use GROUP BY yet you have an INDEX SCAN.  I am
> using a similar query, yet I get a full table scan.  I wonder how they
> are different?

Please send us the results of EXPLAIN ANALYZE the query.  The EXPLAIN
results usually aren't too interesting for degenerate queries.

Also, make sure you have run ANALYZE on your database.

Chris



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