From: Tom Lane <tgl@sss.pgh.pa.us>
To: Ehab Galal <ehabgalal123@hotmail.com>
Cc: pgsql-sql@postgresql.org <pgsql-sql@postgresql.org>
Subject: Re: omitting redundant join predicate
Date: Mon, 05 Nov 2007 11:08:13 -0500
Message-ID: <20749.1194278893@sss.pgh.pa.us> (raw)
In-Reply-To: <BAY138-W453548E0FFC1D11A00D2AD96880@phx.gbl>
References: <BAY138-W43A1A93DB7B84F57B84211968F0@phx.gbl>
<14450.1194194136@sss.pgh.pa.us>
<BAY138-W453548E0FFC1D11A00D2AD96880@phx.gbl>
Ehab Galal <ehabgalal123@hotmail.com> writes:
> what i expected is that the optimizer will use the redundant predicates
> to create the plan, but the execution plan itself will not execute a
> redundant predicate.
> O! I see, it's my mistake. The example i mentioned was not a good example. I tried the equality and it is working well :)
The planner has a great deal more smarts about equality conditions than
inequality conditions. There's more you can do with equalities, and
it's more useful for typical queries.
> I am using postgresql 8.5.1, I am wondering is there is any patch that
> i can run to enable it to put the actual table names instead of
> inner/outer.
Update to 8.2.
regards, tom lane
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To: pgsql-sql@postgresql.org
Cc: tgl@sss.pgh.pa.us, ehabgalal123@hotmail.com
Subject: Re: omitting redundant join predicate
In-Reply-To: <20749.1194278893@sss.pgh.pa.us>
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