What is the lowest salary in departments with average salary greater than the overall average.
return departments ;return salaries of #1 ;return average  of #2 for each #1 ;return average  of #2 ;return #1 where #3 is  higher than #4 ;return salaries of #5 ;return #6 that  is  lowest
['select', 'project', 'group', 'aggregate', 'comparative', 'project', 'filter']