On Fri, 3 Apr 2009, Tom Lane wrote:
> Not unless you have sorted the inputs in some way that has more
> knowledge than the "equal" operator represents. Otherwise you can have
> elements drop out that might still be needed to match to a later
> left-hand element.
Of course. You certainly have to choose a sort order that works. Sorting
by the start field would be sufficient in this case.
Matthew
--
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