On Fri, Oct 4, 2024 at 9:40 PM Robert Haas <robertmh...@gmail.com> wrote: > On Fri, Oct 4, 2024 at 2:20 PM Peter Geoghegan <p...@bowt.ie> wrote: > > On Fri, Oct 4, 2024 at 2:00 PM Alexander Korotkov <aekorot...@gmail.com> > > wrote: > > > Yes, transformAExprIn() does the work to coerce all the expressions in > > > the right part to the same type. Similar logic could be implemented > > > in match_orclause_to_indexcol(). What worries me is whether it's > > > quite late stage for this kind of work. transformAExprIn() works > > > during parse stage, when we need to to resolve types, operators etc. > > > And we do that once. > > > > I agree that it would be a bit awkward. Especially having spent so > > much time talking about doing this later on, not during parsing. That > > doesn't mean that it's necessarily the wrong thing to do, though. > > True, but we also can't realistically use select_common_type() here. I > mean, it thinks that we have a ParseState and that there might be > values with type UNKNOWNOID floating around. By the time we reach the > planner, neither thing is true. And honestly, it looks to me like > that's pointing to a deeper problem with your idea. When someone > writes foo IN (1, 2222222222222222222222222), we have to make up our > mind what type of literal each of those is. select_common_type() > allows us to decide that since the second value is big, we're going to > consider both to be literals of type int8. But that is completely > different than the situation this patch faces. We're now much further > down the road; we have already decided that, say, 1, is and int4 and > 2222222222222222222222222 is an int8. It's possible to cast a value to > a different type if we don't mind failing or have some principled way > to avoid doing so, but it's way too late to reverse our previous > decision about how to parse the characters the user entered. The > original "char *" value is lost to us and the type OID we picked may > already be stored in the catalogs or something.
+1 ------ Regards, Alexander Korotkov Supabase
