Re: patch: Distinguish between unique indexes and unique constraints

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Josh Kupershmidt <schmiddy@gmail.com>, pgsql-hackers@postgresql.org
Date: 2010-04-18T15:23:06Z
Lists: pgsql-hackers
Robert Haas <robertmhaas@gmail.com> writes:
> You know, I've never really understood the difference between these
> two types of things, or why we need to support both.  Which may be
> just because I'm slow?

Unique constraints are defined by the SQL standard, and have a syntax
that can't support a lot of the extensions that CREATE INDEX allows.
There's also restrictions in the information_schema views.
So unifying the two concepts completely would be a mess.

			regards, tom lane