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

Andres Freund wrote:
> 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.

Argh.

> > 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?

Hmm ...

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