Horton

Re: Early WIP/PoC for inlining CTEs

David Fetter <david@fetter.org>

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From: David Fetter <david@fetter.org>
To: Andrew Gierth <andrew@tao11.riddles.org.uk>
Cc: pgsql-hackers@postgresql.org
Date: 2018-07-25T19:14:47Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Prevent inlining of multiply-referenced CTEs with outer recursive refs.

  2. Allow user control of CTE materialization, and change the default behavior.

  3. Split QTW_EXAMINE_RTES flag into QTW_EXAMINE_RTES_BEFORE/_AFTER.

  4. document when PREPARE uses generic plans

Attachments

On Wed, Jul 25, 2018 at 04:18:42PM +0100, Andrew Gierth wrote:
> >>>>> "David" == David Fetter <david@fetter.org> writes:
> 
>  David> Please find attached a version rebased atop 167075be3ab1547e18
>  David> with what I believe are appropriate changes to regression test
>  David> output. The other changes to the regression tests output are
>  David> somewhat puzzling, as they change the actual results of queries.
> 
> Both of those changes are the result of volatile CTEs being inlined more
> than once (in one case, as part of an explicit test to ensure that CTEs
> are being materialized and not multiply evaluated).
> 
> If you look for the XXX comment in the patch, it should be easy to add a
> check that skips inlining if cterefcount > 1 and
> contains_volatile_functions is true.

Thanks for the broad hints!

Please find attached the next version, which passes 'make check'.

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

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