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From: Dirk Lutzebaeck <lutzeb@aeccom.com>
To: pgsql-sql@postgresql.org
Subject: Optimizer question with equivalent joins
Date: Fri, 21 Jun 2002 16:26:03 +0200
Message-ID: <15635.14203.405079.671597@cayambe.core.aeccom.com> (raw)


Hello,

say I have a join which says

    t.a = t.b and t.b = t.c

do I need to give the optimizer a hint by saying it more redundantly

    t.a = t.b and t.b = t.c and t.c = t.a

or is this just counter productive because there is one more join?

In the real world I have 10-20 equivalent joins which would really
blow up if I have to choose the second option.

Dirk


 



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