Tom Lane wrote:
> Comparing the behavior of this to my patch for HEAD, I am coming to the
> conclusion that this is actually a *better* planning method than
> removing the redundant join conditions, even when they're truly
> rendundant! The reason emerges as soon as you look at cases involving
> more than a single join. If we strip the join condition from just one
> of the joins, then we find that the planner insists on doing that join
> last, whether it's a good idea or not, because clauseful joins are
> always preferred to clauseless joins in the join search logic.
Would it be a good idea to keep removing redundant clauses and rethink
the preference for clauseful joins, going forward?
--
Alvaro Herrera http://www.CommandPrompt.com/
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