Re: GEQO status?

Ed Loehr writes:

> What is the status of the genetic algorithm query optimizer?  Is this
> supposed to work well on many-table joins, or has it fallen out of favor
> or in disrepair?  [I'm needing to optimize some large, many-table-join
> queries and wondering time spent configuring/understanding geqo would be
> fruitful...]

I've seen a number of bug reports that would indicate to me the GEQO works
less than perfectly.  I vividly recall how, while working on my own code,
mere additions of dummy clauses like '... AND 5=5' altered query results
in seemingly random ways.  That was admittedly quite a while ago, but the
GEQO code hasn't changed since.  I'd advise you to be *very* careful.

-- 
Peter Eisentraut      peter_e@gmx.net       http://yi.org/peter-e/