On 30/10/2019 09:04, Fabien COELHO wrote: > >> I think possibly what the spec says (and that neither my patch nor >> Peter's implements) is assigning the alias just to the <join column >> list>. > > I think you are right, the alias is only on the identical columns. > > It solves the issue I raised about inaccessible attributes, and > explains why it is only available with USING and no other join variants. > >> So my original example query should actually be: >> >> SELECT a.x, b.y, j.z FROM a INNER JOIN b USING (z) AS j; > > Yep, only z should be in j, it is really just about the USING clause.
My reading of SQL:2016-2 7.10 SR 11.a convinces me that this is the case. My reading of transformFromClauseItem() convinces me that this is way over my head and I have to abandon it. :-(
