Re: Relative ordering in array aggregation

prakashn(at)uci(dot)edu writes:
> I'm using 8.3.3. I came across the array_accum aggregate function in
> the docs:
> http://www.postgresql.org/docs/8.3/interactive/xaggr.html

> This would be very useful to me, but I have a question about ordering
> of values. If I use more than one array_accum in the same select
> clause, is there any reliable correspondence between the order of
> elements in the returned arrays?

As long as you don't use DISTINCT (or, in more recent versions than 8.3,
within-aggregate ordering of the input rows), all aggregates in the same
SELECT list should receive the input rows in the same order.

regards, tom lane