题解 | #获取有奖金的员工相关信息。#

很容易的一个知识交叉运用

select a.emp_no,a.first_name,a.last_name,b.btype,c.salary,
(case 
 when btype = 1 then c.salary * 0.1
 when btype = 2 then c.salary * 0.2
 else c.salary * 0.3
 end
) as bonus
from employees a 
left join emp_bonus b on a.emp_no = b.emp_no 
left join salaries c on a.emp_no = c.emp_no
where b.btype is not null and c.to_date = '9999-01-01';