SQL ORDER BY

ORDER BY 关键字用于对结果集进行排序。

SQL ORDER BY 关键字

ORDER BY 关键字用于对结果集按照一个列或者多个列进行排序。

ORDER BY 关键字默认按照升序对记录进行排序。如果需要按照降序对记录进行排序，您可以使用 DESC 关键字。

SQL ORDER BY 语法

SELECT column_name,column_name
FROM table_name
ORDER BY column_name,column_name ASC|DESC;

演示数据库

在本教程中，我们将使用 runoops样本数据库。

下面是选自 “websites” 表的数据：

+----+----------------+---------------------------+-------+---------+
| id | name           | url                       | alexa | country |
+----+----------------+---------------------------+-------+---------+
|  1 | Google          | https://www.google.cm/    |     1 | USA     |
|  2 | Amazon         | https://z.cn/             |     2 | USA     |
|  3 | 淘宝           | https://www.taobao.com/   |    10 | CN      |
|  4 | 自学教程       | http://runoops.com/       |  5787 | CN      |
|  5 | 微博           | http://weibo.com/         |    18 | CN      |
|  6 | stackoverflow  | http://stackoverflow.com/ |    66 | IND     |
+----+----------------+---------------------------+-------+---------+

ORDER BY 实例

下面的 SQL 语句从 "websites" 表中选取所有网站，并按照 "alexa" 列排序：

SELECT * FROM websites
ORDER BY alexa;

执行输出结果：

mysql> SELECT * FROM websites
    -> ORDER BY alexa;
+----+----------------+---------------------------+-------+---------+
| id | name           | url                       | alexa | country |
+----+----------------+---------------------------+-------+---------+
|  1 | Goole          | https://www.google.cm/    |     1 | USA     |
|  2 | Amazon         | https://z.cn/             |     2 | USA     |
|  3 | 淘宝           | https://www.taobao.com/   |    10 | CN      |
|  5 | 微博           | http://weibo.com/         |    18 | CN      |
|  6 | stackoverflow  | http://stackoverflow.com/ |    66 | IND     |
|  4 | 自学教程       | http://runoops.com/       |  5787 | CN      |
+----+----------------+---------------------------+-------+---------+
6 rows in set (0.00 sec)

ORDER BY DESC 实例

下面的 SQL 语句从 "websites" 表中选取所有网站，并按照 "alexa" 列降序排序：

SELECT * FROM websites
ORDER BY alexa DESC;

执行输出结果：

mysql> SELECT * FROM websites
    -> ORDER BY alexa DESC;
+----+----------------+---------------------------+-------+---------+
| id | name           | url                       | alexa | country |
+----+----------------+---------------------------+-------+---------+
|  4 | 自学教程       | http://runoops.com/       |  5787 | CN      |
|  6 | stackoverflow  | http://stackoverflow.com/ |    66 | IND     |
|  5 | 微博           | http://weibo.com/         |    18 | CN      |
|  3 | 淘宝           | https://www.taobao.com/   |    10 | CN      |
|  2 | Amazon         | https://z.cn/             |     2 | USA     |
|  1 | Google          | https://www.google.cm/    |     1 | USA     |
+----+----------------+---------------------------+-------+---------+
6 rows in set (0.00 sec)

ORDER BY 多列

下面的 SQL 语句从 "websites" 表中选取所有网站，并按照 "country" 和 "alexa" 列排序：

SELECT * FROM websites
ORDER BY country,alexa;

执行输出结果：

mysql> SELECT * FROM websites
    -> ORDER BY country,alexa;
+----+----------------+---------------------------+-------+---------+
| id | name           | url                       | alexa | country |
+----+----------------+---------------------------+-------+---------+
|  3 | 淘宝           | https://www.taobao.com/   |    10 | CN      |
|  5 | 微博           | http://weibo.com/         |    18 | CN      |
|  4 | 自学教程       | http://runoops.com/       |  5787 | CN      |
|  6 | stackoverflow  | http://stackoverflow.com/ |    66 | IND     |
|  1 | Google          | https://www.google.cm/    |     1 | USA     |
|  2 | Amazon         | https://z.cn/             |     2 | USA     |
+----+----------------+---------------------------+-------+---------+
6 rows in set (0.00 sec)