On Sat, Aug 27, 2005 at 11:05:01AM -0400, Tom Lane wrote:
> It could, but it doesn't really have enough information.  We don't
> currently have any model that some operators are more expensive than
> others.  IIRC the only sort of reordering the current code will do
> in a filter condition list is to push clauses involving sub-SELECTs
> to the end.

I was more thinking along the lines of reordering "a AND/OR b" to "b AND/OR
a" if b has lower selectivity than a.

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