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Re: query optimizer - Mailing list pgsql-general

From Tom Lane
Subject Re: query optimizer
Date
Msg-id 14986.1176785338@sss.pgh.pa.us
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In response to query optimizer  ("jungmin shin" <jungmin.shin@gmail.com>)
Responses Re: query optimizer  (Luca Ferrari <fluca1978@infinito.it>)
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"jungmin shin" <jungmin.shin@gmail.com> writes:
> As I see the documentation of postgres, postgres use genetic algorithm for
> query optimization rather than system R optimizer. right?

Only for queries with more than geqo_threshold relations.  The join
search algorithm for smaller queries is a System-R-like dynamic
programming method.

            regards, tom lane

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