直接三表联合,然后判断btype再进行bonus操作
获取有奖金的员工相关信息。
https://www.nowcoder.com/practice/5cdbf1dcbe8d4c689020b6b2743820bf
select *, ( case when btype = 1 then salary * 0.1 when btype = 2 then salary * 0.2 else salary * 0.3 end ) as bonus from( select eb.emp_no,first_name,last_name,btype,salary from salaries as sa join emp_bonus as eb on eb.emp_no = sa.emp_no join employees as em on em.emp_no = eb.emp_no where to_date = '9999-01-01' ) as t1