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Date: Tue, 10 Nov 1998 14:40:01 +0100
From: Christian Saldarini <cristian@gemini.como.polimi.it>
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To: PSQL <pgsql-interfaces@postgreSQL.org>
Subject: need information about storing methods
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Hi,
I'm nowadays tryng to use postgresql to store geographical data to use
them with a gis program (GRASS).
The coordinates of each point are stored in a field that is a
point-type.
Anyone can tell me if postgress uses, for this kind of data, a storing
method like HHCODE, poin-quad-trees (or anything better) , or  it stores
point-data like anything else?
A query like this one:
" SELECT coordinates FROM table WHERE coordinates @ '((1,1),1)'::circle
"
is executed like anything else, processing evry tuple in the table ?
If so, anyone knows how to implement a more complex storing method?

Thanks to all,
Christian Saldarini