2009/11/15 Andrew Gierth <andrew@tao11.riddles.org.uk>:
>>>>>> "Hitoshi" == Hitoshi Harada <umi.tanuki@gmail.com> writes:
>
> Hitoshi> Hi, During reviewing aggregates ORDER BY, I was reading spec
> Hitoshi> and found description like:
>
> Hitoshi> == snip ==
>
> Hitoshi> Of the rows in the aggregation, the following do not qualify:
> Hitoshi> — If DISTINCT is specified, then redundant duplicates.
> Hitoshi> — Every row in which the <value expression> evaluates to the null value.
>
> Hitoshi> == /snip ==
>
> Where did you find that?
In 4.15.4 Aggregate functions. But your snip clarified <array
aggregate function> is special case.
> NOTE 267 -- Null values are not eliminated when computing <array
> aggregate function>. This, plus the optional <sort specification
> list>, sets <array aggregate function> apart from <general set
> function>s.
Regards,
--
Hitoshi Harada
