> Not to put too fine a point on it, but are you talking about the
> original grammar or your modified one? Your modified one is erroneous
> because it will always associate successive UNION/INTERSECT/EXCEPT
> operators left-to-right; this does not meet the SQL spec which insists
> that INTERSECT binds more tightly than the other two. Given that, I'm
> not surprised that the precedences have no effect.
>
> > I don't see precedence in SQL92; set operations
> > seem to be left associative of equal priority.
>
> Better take another look at the <query expression>, <query term>,
> <query primary> hierarchy then...
Is there something here to patch? Hmm, I don't see anything... I will
come back later. :-)
-- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610)
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