Re: Early WIP/PoC for inlining CTEs

On Thu, Jan 10, 2019 at 2:28 PM Andreas Karlsson <andreas(at)proxel(dot)se> wrote:
> 2. Feedback on the new syntax. I am personally fine with the current
> syntax, but it was just something I just quickly hacked together to move
> the patch forward and which also solved my personal uses cases.

Thanks for working on this. I very much want to see this feature go
in. As mentioned by Andres up-thread, TPC-DS makes a lot of use of
CTEs... let me see, 34 queries out of 99 have a WITH clause. These
will hopefully become candidates for parallel query.

I know this is a thorny topic, but I have to say that I am uneasy
about the MATERIALIZED syntax. Here's how you write that in some
other RDBMS that loves hints:

WITH foo AS (SELECT /*+ MATERIALIZE */ ...)

I understood that it was a long standing project policy that we don't
want planner hints, but now we have a proposal to support one with a
top-level non-standard syntax. If we take this syntax, should we not
also accept MATERIALIZED in front of subselects?

-1

--
Thomas Munro
http://www.enterprisedb.com