Re: Lag and lead window functions order by weirdness

Thom Brown <thombrown(at)gmail(dot)com> wrote:

> [...]
> Having a look around, it looks as if Postgres might be misbehaving.
> According to this page,
> http://my.safaribooksonline.com/0596004818/sqlnut2-CHP-4-SECT-3, the ORDER
> BY in the window function's clause shouldn't be having this ordering effect:

> "Furthermore, the order within these groups is defined by an ordering
> clause, but that order only affects function evaluation, and has no effect
> on the order in which rows are returned by the query."

> The behaviour is unexpected from my perspective, but obviously there are
> workarounds. Is anyone able to confirm any of this?

AFAIR, others have already pointed out that without an "OR-
DER BY" clause PostgreSQL can return the result set in *any*
"order" it deems fit. So why don't you use one?

Tim