On Tue, 17 Sep 2019, Alvaro Herrera wrote:
>> Indeed, that seems like a problem, and it's a good question. You can
>> see this on unpatched master with SELECT x.filler FROM
>> (pgbench_tellers AS t JOIN b USING (bid)) AS x.
>
> I'm not sure I understand why that problem is a blocker for this patch.
As discussed on another thread,
https://www.postgresql.org/message-id/flat/2aa57950-b1d7-e9b6-0770-fa592d565dda@2ndquadrant.com
the patch does not conform to spec
SQL:2016 Part 2 Foundation Section 7.10 <joined table>
Basically "x" is expected to include *ONLY* joined attributes with USING,
i.e. above only x.bid should exists, and per-table aliases are expected to
still work for other attributes.
ISTM that this patch could be "returned with feedback".
--
Fabien.