Re: Query not using index

You and Stephan hit it right on the nose - our table has been
maliciously propagated with thousands of faulty values - once gone
index are in use and DB is SPEEDING along  8)

Thanks for your help!!!

-r


On Thu, 10 May 2001 21:49:28 +0000 (UTC), in
comp.databases.postgresql.general you wrote:

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>On Thu, May 10, 2001 at 05:22:07PM -0400, Tom Lane wrote:
>
>> ryan@paymentalliance.net writes:
>> > No the query usually returns between 0 and 5 rows.  Usually not zero -
>> > most often 1.
>>=20
>> Ah.  You must have a few values that are far more frequent (like tens of
>> thousands of occurrences?) and these are throwing off the planner's
>> statistics.
>
>I had a similar situation, where I had a lot of rows with 0's in
>them.  Changing those to NULLs worked wonders.  The planner (or
>statistics gatherer, or something) apparently takes notice of the
>distribution of non-NULL values.
>
>Chris
>
>--=20
>chris@mt.sri.com -----------------------------------------------------
>Chris Jones                                    SRI International, Inc.
>                                                           www.sri.com
>
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