Re: extensible enum types

Andrew Dunstan <andrew@dunslane.net> writes:
> Another thought: could we add a column to pg_type with a flag that's 
> true if the oids are in sort order? Then the comparison routines could 
> just look that up in the type cache and if it's true (as it often will 
> be) just return the oid comparison.

Well, having to do a cache lookup already makes it a couple orders of
magnitude more expensive than an OID comparison.  However, it's hard to
say how much that matters in terms of total application performance.
We really could do with a bit of performance testing here ...
        regards, tom lane