sql笔试

SELECT a.name, a.salary ,a.dept_id FROM emp a WHERE salary<(SELECT AVG(salary) FROM emp WHERE a.dept_id=dept_id GROUP BY dept_id);
     
     SELECT a.name,a.salary ,a.dept_id FROM emp a,(SELECT dept_id, AVG(salary) avge FROM emp GROUP BY dept_id) b WHERE a.salary<avge AND a.dept_id=b.dept_id;

 

查询工资低于所在部门平均工资的员工的姓名和工资

 

员工表emp(id,name,dept_id,salary,) 部门表dept(id,name)