Thread: TODO item: Accept aliases for values in ROW(...) constructor

TODO item: Accept aliases for values in ROW(...) constructor

From
Craig Ringer
Date:
Hi all

Especially with the introduction of json support, but also in the past
with hstore and other things, I've sometimes found myself wishing I
could provide aliases in an anonymous row constructor, e.g.
   ROW(x AS something, y AS somethingelse)

The same thing can be done using a scalar subquery wrapping a
subquery-in-FROM returning a single row, but it's pretty ugly:
   (SELECT r FROM (SELECT x AS something, y AS somethingelse) r)

That's what I've done to produce json a lot, though, and will need to
continue to do so until 9.4's json_build_object etc are in the wild.

While that'll solve the need for json, I'm sure others will come up. So
in case someone feels like exploring the parser a little, does it seem
reasonable to add ROW(...) with aliases to the TODO?

Or, alternately, and perhaps more generally useful, allow rowtype
specifications for anonymous records outside function-call context, like:
 ROW(x1,y1) AS r(x integer, y integer)




Related:
http://stackoverflow.com/q/13227142/398670

-- Craig Ringer                   http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training & Services



Re: TODO item: Accept aliases for values in ROW(...) constructor

From
Craig Ringer
Date:
>     ROW(x AS something, y AS somethingelse)

Apologies, it looks like Pavel already bought this up:

http://www.postgresql.org/message-id/CAFj8pRB1T1W6g0sppn-jEtyzJPLUUz_FxtNbme5Okd3XxVFx_w@mail.gmail.com

and I missed it.

-- Craig Ringer                   http://www.2ndQuadrant.com/PostgreSQL Development, 24x7 Support, Training & Services



Re: TODO item: Accept aliases for values in ROW(...) constructor

From
Pavel Stehule
Date:
Hi Craig

Is there agreement on proposed syntax  ROW(x AS something, y AS somethingelse) ?

I can start work on this topic this week.

Regards

Pavel

2014-11-25 2:33 GMT+01:00 Craig Ringer <craig@2ndquadrant.com>:
>
>
> >     ROW(x AS something, y AS somethingelse)
>
> Apologies, it looks like Pavel already bought this up:
>
> http://www.postgresql.org/message-id/CAFj8pRB1T1W6g0sppn-jEtyzJPLUUz_FxtNbme5Okd3XxVFx_w@mail.gmail.com
>
> and I missed it.
>
> --
>  Craig Ringer                   http://www.2ndQuadrant.com/
>  PostgreSQL Development, 24x7 Support, Training & Services
>
>
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