-- 一表多用
select de.emp_no, dm.emp_no as manager_no, s1.salary as emp_sary ,s2.salary
from dept_emp de,dept_manager dm,salaries s1,salaries s2
where de.dept_no=dm.dept_no
and de.emp_no=s1.emp_no
and dm.emp_no=s2.emp_no
and s1.salary>s2.salary
-- 构建员工工资表 和经理工资表
/**
SELECT a.emp_no, b.manager_no, a.emp_salary, b.manager_salary
FROM
(SELECT de.dept_no, de.emp_no, s.salary AS emp_salary
FROM dept_emp de, salaries s
WHERE de.emp_no=s.emp_no
AND s.to_date='9999-01-01') a,
(SELECT dm.dept_no, dm.emp_no AS manager_no, s.salary AS manager_salary
FROM dept_manager  dm, salaries s
WHERE dm.emp_no=s.emp_no
AND s.to_date='9999-01-01') b
WHERE a.dept_no=b.dept_no
AND a.emp_salary>b.manager_salary;
*/