Re: [HACKERS] patch: function xmltable

Tom Lane wrote:
> Andres Freund <andres@anarazel.de> writes:
> > On 2017-01-24 21:32:56 -0300, Alvaro Herrera wrote:
> >> XMLTABLE is specified by the standard to return multiple rows ... but
> >> then as far as my reading goes, it is only supposed to be supported in
> >> the range table (FROM clause) not in the target list.  I wonder if
> >> this would end up better if we only tried to support it in RT.  I asked
> >> Pavel to implement it like that a few weeks ago, but ...
>
> > Right - it makes sense in the FROM list - but then it should be an
> > executor node, instead of some expression thingy.
>
> +1 --- we're out of the business of having simple expressions that
> return rowsets.

Well, that's it.  I'm not committing this patch against two other
committers' opinion, plus I was already on the fence about the
implementation anyway.  I think you should just go with the flow and
implement this by creating nodeTableexprscan.c.  It's not even
difficult.

--
Álvaro Herrera                https://www.2ndQuadrant.com/
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