题解 | #获取有奖金的员工相关信息。#

• 坑：不要多关联表，此题目中，可以不用员工部门表，salaries中有有效日期

select 
    e.emp_no,
    e.first_name,
    e.last_name,
    b.btype,
    s.salary,
    case when b.btype = 1 then s.salary * 0.1
         when b.btype = 2 then s.salary * 0.2
         else s.salary * 0.3
         end  as bonus
from  employees as e
join salaries as s on s.emp_no = e.emp_no
join emp_bonus as b on e.emp_no = b.emp_no
where s.to_date = '9999-01-01';