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Re: empty string causes planner to avoid index. Makes me sad. - Mailing list pgsql-general

From Jeff Amiel
Subject Re: empty string causes planner to avoid index. Makes me sad.
Date
Msg-id 987026.87261.qm@web65503.mail.ac4.yahoo.com
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In response to Re: empty string causes planner to avoid index. Makes me sad.  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: empty string causes planner to avoid index. Makes me sad.  (Guillaume Lelarge <guillaume@lelarge.info>)
Re: empty string causes planner to avoid index. Makes me sad.  (Stephan Szabo <sszabo@megazone.bigpanda.com>)
Re: empty string causes planner to avoid index. Makes me sad.  (Tom Lane <tgl@sss.pgh.pa.us>)
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--- On Fri, 11/27/09, Tom Lane <tgl@sss.pgh.pa.us> wrote:

> You didn't show us any evidence of that, either.  Both
> of your test
> cases are using the index.

Ok...third try.  The cost when passing in an empty string is SIGNIFICANTLY higher than when not.  Wouldn't seem that
theplanner is using the index effectively. 

Aggregate  (cost=231884.57..231884.57 rows=1 width=0)

versus

Aggregate  (cost=34.83..34.83 rows=1 width=0)


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