Re: Schema variables - new implementation for Postgres 15

Wolfgang Walther <walther@technowledgy.de>

From: Wolfgang Walther <walther@technowledgy.de>

To: Pavel Stehule <pavel.stehule@gmail.com>

Cc: Dmitry Dolgov <9erthalion6@gmail.com>, Tom Lane <tgl@sss.pgh.pa.us>, Peter Eisentraut <peter@eisentraut.org>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Peter Eisentraut <peter.eisentraut@enterprisedb.com>, Sergey Shinderuk <s.shinderuk@postgrespro.ru>, Tomas Vondra <tomas.vondra@enterprisedb.com>, Julien Rouhaud <rjuju123@gmail.com>, dean.a.rasheed@gmail.com, er@xs4all.nl, joel@compiler.org, pgsql-hackers@lists.postgresql.org

Date: 2024-05-31T13:29:29Z

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 →

Allow underscores in integer and numeric constants.
- faff8f8e47f1 16.0 cited
Remove special outfuncs/readfuncs handling of RangeVar.catalogname.
- 3cece34be842 16.0 cited
Remove extra space from dumped ALTER DEFAULT PRIVILEGES.
- 2af33369e794 16.0 cited
Create FKs properly when attaching table as partition
- b0284bfb1db5 16.0 cited
psql: improve tab-complete's handling of variant SQL names.
- 02b8048ba5dc 15.0 cited

Pavel Stehule:
> The session variables can be used in queries, but should be used in 
> PL/pgSQL expressions, and then the mandatory usage in FROM clause will 
> do lot of problems and unreadable code like
> 
> DO $$
> BEGIN
>    RAISE NOTICE '% %', (SELECT x FROM x), (SELECT a,b FROM y);
> 
> END
> $$
> 
> This requirement does variables unusable in PL

I already proposed earlier to only require listing them in FROM when 
there is actually a related FROM.

In this case you could still write:

RAISE NOTICE '% %', x, (SELECT a,b FROM y);

(assuming only x is a variable here)

Best,

Wolfgang