James Stuart <slim2k(at)privatejuris(dot)org> writes:
> UPDATE mentions the RETURNING * syntax but does not mention RETURNING *
> INTO ...
> https://www.postgresql.org/docs/15/sql-update.html
That's because there is no such thing so far as the core SQL parser is
concerned (so if you try it from, say, psql, it won't work).
There is such syntax in plpgsql, and that's where it's documented:
https://www.postgresql.org/docs/current/plpgsql-statements.html#PLPGSQL-STATEMENTS-SQL-ONEROW
regards, tom lane