Michael Nolan <htfoot(at)gmail(dot)com> writes:
> It seems like we're being inconsistent here in allowing 'where xid =
> integer' but not allowing 'where xid != integer'.
Well, if you look into pg_operator you'll soon find that there are
exactly two built-in operators that accept type xid: "=(xid,xid)" and
"=(xid,integer)" (where I'd say the latter is just a kluge).
There hasn't previously been any demand to flesh it out more than that.
Do you have an actual use-case where <> would be helpful, or is this
just experimentation?
regards, tom lane