SELECT * FROM emp; SELECT * FROM dept; 1.查询公司员工工资的最大值,最小值,平均值和总和. SELECT MAX(sal) AS 工资最大值, MIN(sal) AS 工资最小值 , AVG(sal) AS 工资平均值, SUM(sal) AS 工资总和 FROM emp; 2.查询各 job 的员工工资的最大值,最小值,平均值和总和. SELECT job, MAX(sal), MIN(sal) , AVG(sal), SUM(sal) FROM emp