[cpburns2009]

That part of the article doesn't make much sense. It sounds like MySQL finally enabled rational GROUP BYs instead of randomly choosing a row when the grouped rows aren't distinct. This is something at least PostgreSQL has done for ages.

[irishsultan]

Nope, the old mysql was extremely stupid, but the postgres behaviour wasn't that smart because it refused anything not in the group by clause (even when constraints on the table ensure that everything in your select clause can in fact be determined from the columns used to group).