Re: CTE inlining

On Wed, May 03, 2017 at 11:26:27AM -0300, Claudio Freire wrote:
> On Wed, May 3, 2017 at 2:19 AM, Craig Ringer <craig(at)2ndquadrant(dot)com> wrote:
> >> Or we will choose WITH MATERIALIZE, and then the users aware of
> >> the fencing (and using the CTEs for that purpose) will have to
> >> modify the queries. But does adding MATERIALIZE quality as major
> >> query rewrite?
> >
> > Hardly.
> >
> >> Perhaps combining this with a GUC would be a solution. I mean, a
> >> GUC specifying the default behavior, and then INLINE /
> >> MATERIALIZE for individual CTEs in a query?
> >
> > It'd be nice if we could do that for a couple of releases as an
> > interim measure, but people will then get locked into relying on
> > it, and we'll never be able to remove it.
>
> The proposed guc seems like a good idea, without which ORMs that
> support CTEs would be at a loss.

Are you aware of such an ORM which both supports WITH and doesn't also
closely track PostgreSQL development? I'm not.

Even assuming that such a thing exists, it's not at all obvious to me
that we should be stalling and/or putting in what will turn out to be
misfeatures to accommodate it.

Best,
David.
--
David Fetter <david(at)fetter(dot)org> http://fetter.org/
Phone: +1 415 235 3778 AIM: dfetter666 Yahoo!: dfetter
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