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Re: GIN indexscans versus equality selectivity estimation - Mailing list pgsql-hackers

From Robert Haas
Subject Re: GIN indexscans versus equality selectivity estimation
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Msg-id AANLkTi=zfnByKu_D7g1aJJ=P4f=_zLU8f9Zjor=Qrew-@mail.gmail.com
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In response to GIN indexscans versus equality selectivity estimation  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: GIN indexscans versus equality selectivity estimation  (Tom Lane <tgl@sss.pgh.pa.us>)
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On Sun, Jan 9, 2011 at 6:38 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> or we could hack eqsel() to bound the no-stats estimate to a bit less
> than 1.

This seems like a pretty sensible thing to do.  I can't immediately
imagine a situation in which 1.0 is a sensible selectivity estimate in
the no-stats case and 0.90 (say) is a major regression.

-- 
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company

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