> A possible objection to this plan is that if the column-level privileges
> patch doesn't get in, then we're left with a useless column in
> pg_attribute. But an always-null column doesn't cost much of anything,
> and we know that sooner or later we will support per-column ACLs:
> they are clearly useful as well as required by spec. So any
> inefficiency would only be transient anyway.
> Thoughts, objections?
Hrm, I thought if anything we wanted to put them in pg_constraints (at
least inherited ones). Now maybe I have defaults confused with NOT
NULLs... But don't we want to be able to give defaults names and and