> Bruce Momjian <maillist@candle.pha.pa.us> writes:
> >> However, I can't see anything in the SQL92 spec that requires you to
> >> use HAVING intelligently, so maybe this error should be downgraded to
> >> a notice? "HAVING with no aggregates would be faster as a WHERE"
> >> (but we'll do it anyway to satisfy pedants...)
>
> > If we allow them, then people can do things like:
> > HAVING max(a) > b
>
> Er ... what's wrong with that? Assuming b is a group by column,
> of course...
But can we compare aggs and non-aggs? I see now that our code is fine:
select relowner from pg_class group by relowner having max(relowner) = relowner;
This returns the proper result, namely the relowner _having_ the max
id.
Having is using an aggregate and non-aggregate, so when I said we only
support aggregates in the HAVING clause, I was wrong. Looks fine.
-- Bruce Momjian | http://www.op.net/~candle maillist@candle.pha.pa.us | (610)
853-3000+ If your life is a hard drive, | 830 Blythe Avenue + Christ can be your backup. | Drexel Hill,
Pennsylvania19026
