3. Create a complex view that will join and aggregate the two simple views. Note
that there is no reason not to have views of views.
create view dep_sum_v asselect e.department_id,count(1) staff, sum(e.salary) salaries,d.department_name from emp_anon_v e join dept_anon_v don e.department_id=d.department_idgroup by e.department_id,d.department_name;
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