Re: How to use result column names in having cause

On 3/31/06, Andrus <eetasoft(at)online(dot)ee> wrote:
> >> In real application I have long expression instead of 123 and do'nt want
> >> repeat this expression in HAVING clause.
> >
> > You have to repeat the expression. "AS" changes the output name, it
> > can't be used either in the where clause or any other limiting factor
> > like 'having':
>
> Doc about HAVING condition says:
>
> Each column referenced in condition must unambiguously reference a grouping
> colum
>
> HAVING x> AVG(bar) unambiguously references to a grouping column x
>
> Is this bug ? It is very tedious to repeat same column expression in a
> multiple times: one time in column expression, and n times in having clause.

But you're not referencing x, you're trying to use AVG(bar) in your expression.

I assume it's this way because the standard says so.. one of the more
knowledgable list members will be able to confirm/deny this.

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