Re: MERGE lacks ruleutils.c decompiling support!?

On 2023-May-05, Tom Lane wrote:

> I made this function:
>
> CREATE OR REPLACE FUNCTION test_fun()
> RETURNS void
> LANGUAGE SQL
> BEGIN ATOMIC
> MERGE INTO target
> USING source s on s.id = target.id
> WHEN MATCHED THEN
> UPDATE SET data = s.data
> WHEN NOT MATCHED THEN
> INSERT VALUES (s.id, s.data);
> end;
>
> It appears to work fine, but:
>
> regression=# \sf+ test_fun()
> ERROR: unrecognized query command type: 5
>
> and it also breaks pg_dump. Somebody screwed up pretty badly
> here. Is there any hope of fixing it for Monday's releases?
>
> (I'd guess that decompiling the WHEN clause would take a nontrivial
> amount of new code, so maybe fixing it on such short notice is
> impractical. But ugh.)

Hmm, there is *some* code in ruleutils for MERGE, but clearly something
is missing. Let me have a look ...

--
Álvaro Herrera PostgreSQL Developer — https://www.EnterpriseDB.com/