What is the maximum training hours for the students whose training hours is greater than 1000 in different positions?
return the  students ;return training hours  of #1 ;return #1 where #2 is higher than 1000 ;return #3 in  different positions ;return #2 where #1 is equal to #4 ;return maximum of #5
['select', 'project', 'comparative', 'filter', 'comparative', 'aggregate']