"David G. Johnston" <david.g.johnston@gmail.com> writes:
> Unless our docs are completely misleading I'd say that PostgreSQL is being
> conforming while MariaDB is treating information_schema as their version of
> pg_catalog (or at least our system views over top of pg_catalog).
Our project policy is that information_schema should show exactly the
columns mandated by whichever spec version we consider current. If you
see some that are not in your copy of the standard, you probably need a
newer copy. (There are links in our wiki to free draft versions of the
spec, which I think are what most of us rely on in practice.)
MariaDB has a much laxer notion of what compliance to the standard means
here, and AFAIK they feel free to add columns that are not in the
standard. We do not do that.
regards, tom lane