On 2020-08-03 19:44, Wolfgang Walther wrote:
> So given this:
>
> SELECT x.id FROM a LEFT JOIN b USING (id) AS x
>
> will this return NULL or a.id for rows that don't match in b? This
> should definitely be mentioned in the docs and I guess a test wouldn't
> be too bad as well?
This issue is independent of the presence of the alias "x", so I don't
think it has to do with this patch.
There is a fair amount of documentation on outer joins, so I expect that
this is discussed there.
--
Peter Eisentraut
2ndQuadrant, an EDB company
https://www.2ndquadrant.com/