order by实现数据排序

简单排序

mysql> select * from user order by user.id;
+----+-------+
| id | name |
+----+-------+
|  1 | user1 |
|  2 | user2 |
|  3 | user3 |
|  4 | user4 |
| 5 | user5 |
+----+-------+
5 rows in set (0.00 sec)

指定排序方向

搭配desc

mysql> select * from user order by user.id desc;
+----+-------+
| id | name |
+----+-------+
|  5 | user5 |
|  4 | user4 |
|  3 | user3 |
|  2 | user2 |
| 1 | user1 |
+----+-------+
5 rows in set (0.00 sec)

控制输出记录数

• 在给出order by子句时，应该保证它位于from语句之后。如果使用limit，它必须位于order by之后。使用子句的次序将产生错误信息。

mysql> select * from user order by user.id desc limit 2;
+----+-------+
| id | name |
+----+-------+
|  5 | user5 |
| 4 | user4 |
+----+-------+
2 rows in set (0.00 sec)