Re: Refactoring SysCacheGetAttr to know when attr cannot be NULL

Peter Eisentraut <peter(dot)eisentraut(at)enterprisedb(dot)com> writes:
> I think an error message like
> "unexpected null value in system cache %d column %d"
> is sufficient. Since these are "can't happen" errors, we don't need to
> spend too much extra effort to make it prettier.

I'd at least like to see it give the catalog's OID. That's easily
convertible to a name, and it doesn't tend to move around across PG
versions, neither of which are true for syscache IDs.

Also, I'm fairly unconvinced that it's a "can't happen" --- this
would be very likely to fire as a result of catalog corruption,
so it would be good if it's at least minimally interpretable
by a non-expert. Given that we'll now have just one copy of the
code, ISTM there's a good case for doing the small extra work
to report catalog and column by name.

regards, tom lane