On Tue, Aug 7, 2012 at 5:07 PM, Stefan Keller <sfkeller@xxxxxxxxx> wrote: > Hi Craig > > Clever proposal! > I slightly tried to adapt it to the hstore involved. > Now I'm having a weird problem that PG says that "relation 'p' does not exist". > Why does PG recognize table b in the subquery but not table p? > Any ideas? I don't think it does recognize b, either. It just fell over on p before it had a chance to fall over on b. I think you have to use WITH if you want to reference the same subquery in multiple FROMs. Another approach would be to add explicit conditions for there being at least 1 school and 1 pharmacy within distance. There can't be >1 unless there is >=1, but the join possibilities for >=1 (i.e. "where exists" rather than "where (select count(*)...)>1" ) are much more attractive than the ones for >1. Cheers, Jeff -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance