On Wed, Jul 25, 2018 at 07:42:37AM +0200, David Fetter wrote:
> Please find attached a version rebased atop 167075be3ab1547e18 with
> what I believe are appropriate changes to regression test output. The
> other changes to the regression tests output are somewhat puzzling, as
> they change the actual results of queries. I've also attached both
> the "leftover" diff and the files to which it should be applied.
I think the SQL programmer needs some control over whether a CTE is:
- a materialized view -- and therefore a barrier
- a view (which can then be inlined by the optimizer)
It is possible to add a keyword for this purpose in the WITH syntax:
WITH VIEW (...) AS a_view
, MATERIALIZED VIEW (...) AS a_barrier
...;
This would be a lot like creating TEMP views, but without the catalog
overhead.
(I wonder how hard it would be to partiion the OID namespace into
temp/persistent ranges so that temp schema elements need not be written
into the catalog.)
Nico
--
