Andrew Gierth <andrew@tao11.riddles.org.uk> writes:
> "Peter" == Peter Eisentraut <peter_e@gmx.net> writes:
> Peter> This is exactly the syntax that is in the spec AFAICT.
> Right. The spec defines this syntax for array_agg and xmlagg (only).
Cool, I had forgotten that they added that in the latest revisions.
I withdraw the complaint that this patch goes too far beyond the spec.
> But it would be entirely unreasonable, the way postgres works, to
> implement ORDER BY for only specific aggregates.
Quite. This is another instance of the thing I complained of before,
that the SQL committee likes to define the behavior of specific
aggregates instead of inducing a generic aggregate-behavior definition.
So we're on our own to extract one, and this proposal seems pretty
reasonable to me: it's useful and it's consistent with the query-level
behavior of DISTINCT and ORDER BY.
regards, tom lane