Tom Lane wrote:
> Heikki Linnakangas <heikki@enterprisedb.com> writes:
>> Another question is, what should cmin and cmax system columns return?
>
> If we're going to fool with these, I'd like to renew the suggestion I
> made awhile back that none of the system columns should have explicit
> entries in pg_attribute, but rather their lookup should be special-cased
> in the parser. And whatever we do with cmin/cmax, the infomask should
> become exposed as well.
I just looked back at that discussion in the archives
(http://archives.postgresql.org/pgsql-hackers/2005-02/msg00615.php).
What was the original reason for the proposal? Space savings?
We could rename pg_attribute as pg_userattribute, and remove all the
system attributes from that. To stay backwards-compatible, we could have
a pg_attribute view on top of that contained the system attributes as well.
--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com