7.ORDER BY 子句

ORDER BY 语句

ORDER BY 语句用于根据指定的列对结果集进行排序。

ORDER BY 语句默认按照升序对记录进行排序。

如果您希望按照降序对记录进行排序，可以使用 DESC 关键字。

1.以时间显示，升序

mysql> select * from Orders order by OrderDate;
+------+------------+------------+----------+
| O_Id | OrderDate  | OrderPrice | Customer |
+------+------------+------------+----------+
|    1 | 2008-07-22 |    1000.00 | Carter   |
|    6 | 2008-11-22 |    1000.00 | Adams    |
|    5 | 2008-11-29 |    1000.00 | Bush     |
|    2 | 2008-12-24 |    1000.00 | Bush     |
|    3 | 2008-12-26 |    1000.00 | tom      |
|    4 | 2008-12-27 |    1000.00 | Carter   |
|    1 | 2008-12-29 |    1000.00 | Bush     |
+------+------------+------------+----------+
7 rows in set (0.04 sec)

2.以字母顺序显示Customer名称，并以数字顺序显示顺序号（OrderDate）：

mysql> select * from Orders order by Customer,OrderDate;
+------+------------+------------+----------+
| O_Id | OrderDate  | OrderPrice | Customer |
+------+------------+------------+----------+
|    6 | 2008-11-22 |    1000.00 | Adams    |
|    5 | 2008-11-29 |    1000.00 | Bush     |
|    2 | 2008-12-24 |    1000.00 | Bush     |
|    1 | 2008-12-29 |    1000.00 | Bush     |
|    1 | 2008-07-22 |    1000.00 | Carter   |
|    4 | 2008-12-27 |    1000.00 | Carter   |
|    3 | 2008-12-26 |    1000.00 | tom      |
+------+------------+------------+----------+
7 rows in set (0.00 sec)

3.以逆字母顺序显示Customer名称：

mysql> select * from Orders order by Customer desc ;
+------+------------+------------+----------+
| O_Id | OrderDate  | OrderPrice | Customer |
+------+------------+------------+----------+
|    3 | 2008-12-26 |    1000.00 | tom      |
|    1 | 2008-07-22 |    1000.00 | Carter   |
|    4 | 2008-12-27 |    1000.00 | Carter   |
|    1 | 2008-12-29 |    1000.00 | Bush     |
|    2 | 2008-12-24 |    1000.00 | Bush     |
|    5 | 2008-11-29 |    1000.00 | Bush     |
|    6 | 2008-11-22 |    1000.00 | Adams    |
+------+------------+------------+----------+
7 rows in set (0.00 sec)

4.以逆字母顺序显示Customer名称，并以数字顺序显示顺序号OrderDate：

mysql> select * from Orders order by Customer desc, OrderDate asc ;
+------+------------+------------+----------+
| O_Id | OrderDate  | OrderPrice | Customer |
+------+------------+------------+----------+
|    3 | 2008-12-26 |    1000.00 | tom      |
|    1 | 2008-07-22 |    1000.00 | Carter   |
|    4 | 2008-12-27 |    1000.00 | Carter   |
|    5 | 2008-11-29 |    1000.00 | Bush     |
|    2 | 2008-12-24 |    1000.00 | Bush     |
|    1 | 2008-12-29 |    1000.00 | Bush     |
|    6 | 2008-11-22 |    1000.00 | Adams    |
+------+------------+------------+----------+
7 rows in set (0.00 sec)