SQL语句排序的有关问题

create table EmployeeInfo(id int ,EmpName varchar(20),EmpDate varchar(10),EmpPlace varchar(20))insert into EmployeeInfo values(1,'人员1','2012-09-25','北京');insert into EmployeeInfo values(2,'人员2','2012-09-26','北京');insert into EmployeeInfo values(3,'人员3','2012-09-26','北京');insert into EmployeeInfo values(4,'人员4','2012-09-25','上海');insert into EmployeeInfo values(5,'人员5','2012-09-25','广州');insert into EmployeeInfo values(6,'人员6','2012-09-26','上海');