Re: Suggestions wanted for 7.2.4 query

From: Josh Berkus <josh(at)agliodbs(dot)com>
To: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: PgSQL Performance ML <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Suggestions wanted for 7.2.4 query
Date: 2003-05-05 17:59:11
Message-ID: 200305051059.11751.josh@agliodbs.com
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Folks,

> That may be solvable without forcing a seq scan on "events", simply by
> overdetermining the criteria on date. That is, I can't apply the date
> criteria to "events" because that would require running date calucations on
> each row forcing a seq scan ( i.e. (event_date + duration) between date_one
> and date_two would require a seq scan), but I can apply a broadend version
of
> the criteria to "events" ( i.e. event_date between (date_one - 1 month) and
> (date_two + 1 day)) which would give the planner the idea that it is
> returning a minority of rows from "events".

If anyone is interested, the above idea worked.

--
-Josh Berkus
Aglio Database Solutions
San Francisco

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