Re: [SQL] Joining bug????

From: jwieck(at)debis(dot)com (Jan Wieck)
To: djackson(at)cpsgroup(dot)com (Jackson, DeJuan)
Cc: jwieck(at)debis(dot)com, caffeine(at)toodarkpark(dot)org, selkovjr(at)mcs(dot)anl(dot)gov, pierre(at)desertmoon(dot)com, pgsql-sql(at)postgreSQL(dot)org
Subject: Re: [SQL] Joining bug????
Date: 1998-10-28 18:38:00
Message-ID: m0zYaTp-000EBPC@orion.SAPserv.Hamburg.dsh.de
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> > But it's interesting. I'll do some tests on it and try to
> > find out whether parsing of complicated WHERE clauses is that
> > costly that it can be the reason. Seems the rule system is
> > quicker than the parser :-)
> >
> What kind of speed increases are people seeing in their queries?
> I've actually never created a view in PostgreSQL (say he with head hung
> low).

Used a view that is a join of 5 tables. There is absolutely
no difference between using the view or the equivalent select
from the tables directly in what -s prints as times.

There must be something else that causes the speedup
reported. Maybe another ordering in the qualifications when
using the view. The view qual's are added last to the
original queries qual. Putting them the other way round in
the query might produce another join order.

Jan

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