Re: MERGE ... RETURNING

Jeff Davis <pgsql@j-davis.com>

From: Jeff Davis <pgsql@j-davis.com>
To: Dean Rasheed <dean.a.rasheed@gmail.com>, Gurjeet Singh <gurjeet@singh.im>
Cc: Isaac Morland <isaac.morland@gmail.com>, PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Date: 2023-10-24T19:10:59Z
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. Add RETURNING support to MERGE.

  2. doc: Improve a couple of places in the MERGE docs.

  3. doc: improve description of privileges for MERGE and update glossary.

  4. Fix RLS policy usage in MERGE.

  5. Fix leak of LLVM "fatal-on-oom" section counter.

  6. Implement outer-level aggregates to conform to the SQL spec, with

On Wed, 2023-08-23 at 11:58 +0100, Dean Rasheed wrote:
> Updated version attached, fixing an uninitialized-variable warning
> from the cfbot.

I took another look and I'm still not comfortable with the special
IsMergeSupportFunction() functions. I don't object necessarily -- if
someone else wants to commit it, they can -- but I don't plan to commit
it in this form.

Can we revisit the idea of a per-WHEN RETURNING clause? The returning
clauses could be treated kind of like a UNION, which makes sense
because it really is a union of different results (the returned tuples
from an INSERT are different than the returned tuples from a DELETE).
You can just add constants to the target lists to distinguish which
WHEN clause they came from.

I know you rejected that approach early on, but perhaps it's worth
discussing further?

Regards,
	Jeff Davis