Horton

Re: 2 Selects 1 is faster, why?

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Keith Gray <keith@heart.com.au>
Cc: Masaru Sugawara <rk73@sea.plala.or.jp>, Alvar Freude <alvar@a-blast.org>, pgsql-sql@postgresql.org
Date: 2002-06-28T03:52:40Z
Lists: pgsql-sql 
Keith Gray <keith@heart.com.au> writes:
> ...but is it true that if you place the filter clause first,
> the join will not have to complete the whole table?

PG's planner does not pay attention to the ordering of WHERE clauses;
it will do what it thinks best with them in any case.

			regards, tom lane