Using UNION for multi query

[Yamin AbuDaqqa]

How do I use UNION for multi query

example

set @dept_id='d002';
call new_procedure_total_emp_dept(@dept_id ,@result);

(select dn,staff_title, count(staff_title), (count(staff_title)/@result)*100 from
(
SELECT d.dept_name as dn, ti.title as staff_title FROM dept_emp de
join titles ti using (emp_no)
-- join employees emp using (emp_no)
join departments d on d.dept_no = de.dept_no
where de.dept_no = 'd002'
group by de.emp_no
) as staff_no
group by staff_title
)

union

(
select dn,staff_title, count(staff_title), (count(staff_title)/17786)*100 from
(
SELECT d.dept_name as dn, ti.title as staff_title FROM dept_emp de
join titles ti using (emp_no)
-- join employees emp using (emp_no)
join departments d on d.dept_no = de.dept_no
where de.dept_no = 'd003'
group by de.emp_no
) as staff_no
group by staff_title
)
;