select * from 表名 order by 字段名 desc //降序
select * from 表名 order by 字段名 asc //升序
降序:
select * from emp order by empid desc; //按empid这一列的值降序来排列查询出emp表
升序:
select * from emp order by age asc; //按age这一列的值升序来排列查询出emp表
select * from emp order by age ; //默认为升序