Message-ID: <414921F9.400@joeconway.com>
Date: Wed, 15 Sep 2004 22:17:45 -0700
From: Joe Conway <mail@joeconway.com>
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To: Christopher Browne <cbbrowne@acm.org>
Cc: pgsql-performance@postgresql.org
Subject: Re: Data Warehouse Reevaluation - MySQL vs Postgres --
References: <20040914223333.GL56059@decibel.org>
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Christopher Browne wrote:
> In the last exciting episode, mail@joeconway.com (Joe Conway) wrote:
>>That's exactly what we're doing, but using inherited tables instead of
>>a union view. With inheritance, there is no need to rebuild the view
>>each time a table is added or removed. Basically, in our application,
>>tables are partitioned by either month or week, depending on the type
>>of data involved, and queries are normally date qualified.

> Where does the constraint come in that'll allow most of the data to be
> excluded?

Not sure I follow this.

> Or is this just that the entries are all part of "bigtable" so that
> the self join is only 2-way?

We don't have a need for self-joins in our application. We do use a 
crosstab function to materialize some transposed views of the data, 
however. That allows us to avoid self-joins in the cases where we might 
otherwise need them.

Joe