"Jim C. Nasby" <jnasby@pervasive.com> writes:
> On Fri, Aug 04, 2006 at 02:40:30PM -0400, Tom Lane wrote:
>> I would argue that turning on constraint_exclusion ought to instruct
>> the planner to catch this sort of thing, whereas when it's off we
>> ought not expend the cycles. I have a preliminary patch (below)
>> that seems to fix it.
> How many cycles are we talking about here? Is it even worth the GUC?
I think so. On simple queries the optimization will *never* fire,
and there's no point in doing the search. People who are running
complex queries will want to turn it on, but the mysql-equivalent
crew will just find it a waste of cycles.
regards, tom lane