Tied aggregates and sort order

Question

Accepted Answer

East totals 500 + 200 = 700 and West totals 300 + 400 = 700. Both groups have the same total, so ORDER BY total DESC produces a tie - the database may return them in any order. In practice most engines return East before West here (alphabetical tiebreak on region), giving East | 700 then West | 700. The alias 'total' is usable in ORDER BY because ORDER BY is evaluated after SELECT.