Re: ROWS FROM(): A Foolish (In)Consistency? - Mailing list pgsql-hackers

On Tue, Oct 20, 2015 at 11:03 AM, David Fetter <david@fetter.org> wrote:
> On Tue, Oct 20, 2015 at 10:52:05AM -0400, Robert Haas wrote:
>> On Mon, Oct 19, 2015 at 8:02 PM, Jim Nasby <Jim.Nasby@bluetreble.com> wrote:
>> > On 10/19/15 1:07 PM, David Fetter wrote:
>> >>
>> >> What I'd like to do is lift the restriction on ROWS FROM(), which
>> >> currently requires that the stuff inside the parentheses set-returning
>> >> functions, so constructs something like the following would actually work:
>> >>
>> >> SELECT *
>> >> FROM
>> >> ROWS FROM (
>> >>      (VALUES (...), ..., (...)),
>> >>      (SELECT ... ),
>> >>      (INSERT ... RETURNING ... ),
>> >>      my_srf()
>> >> )
>> >> AS t(...)
>> >>
>> >> would actually work.
>> >
>> >
>> > There's been a few places where I would have found that handy.
>>
>> Why not just use a subquery with UNION ALL?
>
> Because UNION ALL glues the queries vertically, not horizontally.

Ah.  I get it now.  Thanks for clarifying.

-- 
Robert Haas
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