Re: Joining against a view that uses an aggregate - performance issue

Here's a much smaller self-contained example of the problem:

https://gist.github.com/joevandyk/06e1e26219726f11917e/raw/e9b279c2f2776d5825a6adbb04c7a41201f8cd24/gistfile1.txt

Joe

On Fri, Mar 8, 2013 at 4:17 PM, Joe Van Dyk <joe(at)tanga(dot)com> wrote:

>
> https://gist.github.com/joevandyk/070e4728c4c9fe1bf086/raw/8b1ecf4b2d4fd127a22cb19abe948c29d78c2158/gistfile1.txtsummarizes the problem.
>
> andres on #postgresql says that making #2 use a faster plan shouldn't be
> hard, but he doesn't seem #3 happening.
>
> I was surprised about #2 not being faster, andres said "Afaics its this
> restriction: "1. The qual must not contain any subselects (mainly because
> I'm not sure it will work correctly: sublinks will already have been
> transformed into subplans in the qual, but not in the subquery)." in
> qual_is_pushdown_safe"
>
> Not sure if there's anything to be done here, just thought I'd post in
> case anyone has any ideas. In an ideal world, I'd be able to write version
> #3.
>
> Joe
>