Without seeing the schema or anything, a similar
query to your first one appears to run on my
Postgres 7.0.2 setup. It's probably worth upgrading.
On Wed, 30 Aug 2000, J. Fernando Moyano wrote:
> I try this on my system: (Postgres 6.5.2, Linux)
>
> "select n_lote from pedidos except select rp.n_lote from relpedidos rp,
> relfacturas rf where rp.n_lote=rf.n_lote group by rp.n_lote having
> sum(rp.cantidad)=sum(rf.cantidad)"
>
> and I get this result:
>
> ERROR: rewrite: comparision of 2 aggregate
> columns not supported
>
> but if I try this one:
>
> "select rp.n_lote from relpedidos rp, relfacturas rf where
> rp.n_lote=rf.n_lote group by rp.n_lote having sum(rp.cantidad)=sum(rf.cantidad)"
>
> It's OK !!
>
> What's up???
> Do you think i found a bug ???
> Do exists some limitation like this in subqueries??
>
> (Perhaps Postgres don't accept using aggregates in subqueries ???)
>
> I tried this too:
>
> "select n_lote from pedidos where n_lote not in (select rp.n_lote from
> relpedidos rp, relfacturas rf where rp.n_lote=rf.n_lote group by rp.n_lote
> having sum(rp.cantidad)=sum(rf.cantidad))"
>
> but the result was the same !
>
> And i get the same error message (or similar) when i try other variations.