Hackers,
So, I can create a custom aggregate "first" and do this:
SELECT first(val order by ts desc) ...
And I can do this:
SELECT first_value(val) OVER (order by ts desc)
... but I can't do this:
SELECT first_value(val order by ts desc)
... even though under the hood, it's the exact same operation.
--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com