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

Started by Craig Ringerabout 11 years ago3 messages
#1Craig Ringer
craig@2ndquadrant.com

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

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#2Craig Ringer
craig@2ndquadrant.com
In reply to: Craig Ringer (#1)
Re: TODO item: Accept aliases for values in ROW(...) constructor

ROW(x AS something, y AS somethingelse)

Apologies, it looks like Pavel already bought this up:

/messages/by-id/CAFj8pRB1T1W6g0sppn-jEtyzJPLUUz_FxtNbme5Okd3XxVFx_w@mail.gmail.com

and I missed it.

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#3Pavel Stehule
pavel.stehule@gmail.com
In reply to: Craig Ringer (#2)
Re: TODO item: Accept aliases for values in ROW(...) constructor

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:

/messages/by-id/CAFj8pRB1T1W6g0sppn-jEtyzJPLUUz_FxtNbme5Okd3XxVFx_w@mail.gmail.com

Show quoted text

and I missed it.

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PostgreSQL Development, 24x7 Support, Training & Services

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