On Thu, Feb 23, 2017 at 10:37:16AM +0100, Bernd Helmle wrote: > Am Mittwoch, den 22.02.2017, 22:17 -0500 schrieb Tom Lane: > > [ shrug... ] Well, I won't resist this hard as long as it's done > > competently, which to me means "the subquery name doesn't conflict > > with > > anything else". Not "it doesn't conflict unless you're unlucky > > enough > > to have used the same name elsewhere". There are a couple ways we > > could > > achieve that result, but the submitted patch fails to. > > Right, i'm going to give it a try then. Currently i see these options: > > * Validate any generated alias against a list of explicit alias names. > > This means we have to collect explicit alias names in, say a hashtable, > and validate a generated name against potential collisions and retry. > Or better, generate the name in a way that doesn't produce a collision > with this list.
There's another option: * Gensym an alias name, and if the compilation fails with that alias name as a conflict, try again with a new gensym'ed name. > * Don't force/generate an alias at all. That seems like a lot of work. Nico -- -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers