题解 | #获取有奖金的员工相关信息。#

两种方法IF和CASE WHEN

SELECT em.emp_no,em.first_name,em.last_name,eb.btype,sa.salary,
        (case eb.btype when 1 then sa.salary*0.1
                      when 2 then sa.salary*0.2
        else sa.salary*0.3
        end) bonus
        #IF(eb.btype=1,0.1*sa.salary,IF(eb.btype=2,0.2*sa.salary,0.3*sa.salary)) bonus
FROM employees em JOIN emp_bonus eb ON em.emp_no=eb.emp_no
    LEFT JOIN salaries sa ON em.emp_no=sa.emp_no
WHERE sa.to_date ='9999-01-01'