Show each county along with the number of schools and total enrollment in each county.
return counties ;return schools in #1 ;return number of  #2 for each  #1 ;return enrollments of  #2 ;return sum of  #4 for each  #1 ;return #1 ,  #3 ,   #5
['select', 'project', 'group', 'project', 'group', 'union']