pá 11. 1. 2019 v 20:11 odesílatel Robert Haas <robertmh...@gmail.com> napsal:
> On Fri, Jan 11, 2019 at 2:04 PM Andres Freund <and...@anarazel.de> wrote: > > > Maybe we could consider a more extensible syntax that is attached to > > > the contained SELECT rather than the containing WITH. Then CTEs would > > > be less special; there'd be a place to put hints controlling top-level > > > queries, subselects, views etc too (perhaps eventually join hints, > > > parallelism hints etc, but "materialize this" would be just another > > > one of those things). That'd be all-in. > > > > I think you have some purity arguments here, but the likelihood of us > > developing a full-blown solution is not that high, and the lack of > > inlinable CTEs is *really* hurting us. As long as the design doesn't > > block a full solution, if we go there, I think it's a very acceptable > > blemish in comparison to the benefits we'd get. > > Also, it seems to me that this is properly a property of the > individual WITH clause, not the query as a whole. > > I mean I suppose we could do > > WITH or_with_out_you OPTIONS (materialized false) AS (SELECT 'mariah > carey') SELECT ... > > That'd allow for extensibility, have the write scope, and look like > what we do elsewhere. It looks a little less elegant than > > WITH cte_name [[NOT] MATERIALIZED] AS (query) main_query... > > ...but maybe elegance for extensibility is a good trade. > I like this explicit syntax (both variant can be used). From my perspective, it is much better than hints in comments. Regards Pavel > > -- > Robert Haas > EnterpriseDB: http://www.enterprisedb.com > The Enterprise PostgreSQL Company > >
