Cedric,
> See this example:
> # create table foo (i int, t timestamptz);
> # insert into foo select n, now() from generate_series(1,10) g(n);
> # select i, first_value(i) over (order by t desc) from foo;
> # select i, first_value(i) over (order by t desc ROWS between 0 PRECEDING and
> UNBOUNDED FOLLOWING) from foo;
>
> What do you expect "SELECT first(val order by ts desc)" to output ?
>
Ah, right, I see what you mean. Yeah, I was doing queries without peer
rows, so it looked the same to me, and it uses some of the same
machinery. But of course it's not completely the same.
--
Josh Berkus
PostgreSQL Experts Inc.
http://pgexperts.com