create type ot is object (
   employee_id integer,
   last_name varchar2(100),
   department_id integer,
   salary number)

create type nt is table of ot

declare
   emps nt;
begin
   select ot (employee_id, last_name, department_id, salary) 
     bulk collect into emps
     from hr.employees;
     
   for rec in (
   select d.department_name, sum (e.salary) total_salary
     from hr.departments d, table (emps) e
    where d.department_id = e.department_id
    group by d.department_name)
   loop
       dbms_output.put_line (rec.department_name || ' - ' || rec.total_salary);
   end loop;
end;