If a person whose head and chest are above water is behind a stingray in the ocean.
return person ;return #1 whose head is  above water ;return #2 whose chest is  above water ;return #3 that is  behind a  stingray ;return #4 in  the  ocean ;return number of #5 ;return is  #6 equal to one
['select', 'filter', 'filter', 'filter', 'filter', 'aggregate', 'boolean']