what river flows through mali niger and nigeria?
return river ;return mali ;return niger ;return nigeria ;return #1 that flows through #2 ;return #1 that flows through #3 ;return #1 that flows through #4 ;return #1 in  both  #5 and #6 ;return #1 in  both  #8 and #7
['select', 'select', 'select', 'select', 'filter', 'filter', 'filter', 'intersection', 'intersection']