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From: Luke Lonergan <llonergan@greenplum.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
To: John Major <major@cbio.mskcc.org>
Cc: pgsql-performance@postgresql.org
Subject: Re: Help w/speeding up range queries?
Date: Tue, 31 Oct 2006 21:26:04 -0800
Message-ID: <C16D6FEC.5991%llonergan@greenplum.com> (raw)
In-Reply-To: <12189.1162355349@sss.pgh.pa.us>

John,

On 10/31/06 8:29 PM, "Tom Lane" <tgl@sss.pgh.pa.us> wrote:

>> 'chrX' and StartPosition > 1000500 and EndPosition < 2000000;
> 
> Also, there's the PostGIS stuff, though it might be overkill for what
> you want.

Oops - I missed the point earlier.  Start and End are separate attributes so
this is like an unbounded window in a Start,End space.  PostGis provides
quadtree indexing would provide a terse TID list but you still have the
problem of how to ensure that the heap tuples being scanned are efficiently
retrieved, which would only happen if they are grouped similarly to the
retrieval pattern, right?

- Luke





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