group by Region having avg(Salary)>40000
-- 3).按照部门分组,查看每个部门的平均工资
select Department,avg(Salary) from...EmpTable group by Department
--4).同时按照地区和部门分组,显示如山东地区人力资源部的平均工资的信息
select Region,Department,avg(Salary...) from EmpTable group by Region,Department
--5).同时按照地区和部门、地区、部门分组
select Region,Department,avg(Salary...,sum(Salary) from EmpTable group by rollup(Region)
--Region
--不分组
select Region,Department,sum(Salary...) from EmpTable group by rollup(Region,Department)
--Region,Department
--Region
--不分组
-- rollup(A,B,