题解 | #获取有奖金的员工相关信息。#

SELECT e.emp_no, e.first_name, e.last_name, b.btype, s.salary,
    (CASE b.btype WHEN 1 THEN s.salary*0.1
                  WHEN 2 THEN s.salary*0.2
                  ELSE s.salary*0.3 END) AS bonus
FROM employees AS e
    INNER JOIN emp_bonus AS b ON e.emp_no = b.emp_no
    INNER JOIN salaries AS s ON e.emp_no = s.emp_no AND s.to_date = '9999-01-01';