Re: PostgreSQL vs MySQL, and FreeBSD

On Nov 16, 2007 3:36 PM, Josh Trutwin <josh@trutwins.homeip.net> wrote:
> > Agreed.  IMHO, there's nothing wrong with nested-loop join as long
> > as it's being used properly.
>
> Can you explain further please?  (I'm not disagreeing with you, just
> want to know when nested loops are not used properly - does the
> planner make mistakes that you have to watch out for?)

As long as statistics are updated properly, it's generally not an
issue.  You just don't want the system using a nested-loop join
incorrectly (like when table sizes are equal, the outer table is
larger than the inner table, or the inner table itself is overly
large).

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Jonah H. Harris, Sr. Software Architect | phone: 732.331.1324
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