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Re: Question about Bitmap Heap Scan/BitmapAnd

From: "Guillaume Smet" <guillaume(dot)smet(at)gmail(dot)com>
To: "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: "Alvaro Herrera" <alvherre(at)commandprompt(dot)com>, pgsql-performance(at)postgresql(dot)org
Subject: Re: Question about Bitmap Heap Scan/BitmapAnd
Date: 2007-02-15 18:09:15
Message-ID: 1d4e0c10702151009n54772ac0rece99a7af35f3399@mail.gmail.com (view raw or flat)
Thread:
Lists: pgsql-performance
On 2/15/07, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> I think that the
> answer is probably "because the index is lossy for this operator,
> so it has to be checked even if the bitmap didn't become lossy".
> You'd have to check the GIST opclass definition to be sure.

Any idea on what I have to look for (if it's of any interest for
anyone, otherwise, I can live with your answer)?

Thanks.

--
Guillaume

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Subject: Re: Question about Bitmap Heap Scan/BitmapAnd
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