>>>> In standard SQL you have to
>>>> write GROUP BY ... and list every single column you need from the master
>>>> table.
This thread seems to have gone off on a tangent that depends on the
assumption that the above is a correct statement. It's not. It *was*
true, in SQL92, but SQL99 lets you omit unnecessary GROUP BY columns.
The gripe against mysql, I think, is that they don't enforce the
conditions that guarantee the query will give a unique result.
The gripe against postgres is that we haven't implemented the SQL99
semantics yet.
regards, tom lane