Re: Broken selectivity with special inet operators - Mailing list pgsql-bugs

From Josh Berkus
Subject Re: Broken selectivity with special inet operators
Date
Msg-id 4E7A833B.1010609@agliodbs.com
Whole thread Raw
In response to Re: Broken selectivity with special inet operators  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Broken selectivity with special inet operators  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-bugs
> If you mean the indexscan optimization, we do know how to estimate the
> cost of the indexscans, because that depends mostly on the behavior of
> the added < or > condition(s).  This does not imply knowing how to
> estimate the behavior of >>= itself.

If we can estimate the cost of the indexscan, why can't we estimate the
rowcount?  Sorry if I'm being dense here, but I really don't understand
how the special operator code works at all.

--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com

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