I was wondering about the GROUP BY statement, and being Friday, i thought i would ask it here.
SELECT Moo, SUM(Cow) FROM Moo; will fail because there is a COLUMN and aggregate with no corresponding GROUP BY. However, the GROUP BY can be inferred...even SQL Developer will (when the option is checked) write the obvious GROUP BY clause for you! The GROUP BY clause seems as redundant as the "SELECT * FROM" of an EXISTS clause.
Imagine i had my way: the GROUP BY clause would be optional, that is, an inferred GROUP BY clause would be acceptable. In such a case when would a GROUP BY clause be required? Put another way, when can an explicit GROUP BY clause produce different results than an inferred one?