Re: [HACKERS] Implement targetlist SRFs using ROWS FROM() (wasChanged SRF in targetlist handling)

On 2017-01-16 16:04:34 -0300, Alvaro Herrera wrote:
> Andres Freund wrote:
> > On 2017-01-16 12:17:46 -0300, Alvaro Herrera wrote:
> > > Hmm.  I wonder if your stuff could be used as support code for
> > > XMLTABLE[1].
> > 
> > I don't immediately see what functionality overlaps, could you expand on
> > that?
> 
> Well, I haven't read any previous patches in this area, but the xmltable
> patch adds a new way of handling set-returning expressions, so it
> appears vaguely related.

Ugh. That's not good - I'm about to remove isDone. Like completely.
That's why I'm actually working on all this, because random expressions
returning more rows makes optimizing expression evaluation a lot harder.

> These aren't properly functions in the current sense of the word,
> though.

Why aren't they? Looks like it'd be doable to do so, at least below the
parser level?


Regards,

Andres