9、MySQL的数据排序

1、单个字段的排序order by desc降序 ； 0-9，a-z， A-Z

mysql> select prod_name, prod_price from products order by prod_price;
+----------------+------------+
| prod_name      | prod_price |
+----------------+------------+
| Carrots        | 2.50       |
| TNT (1 stick)  | 2.50       |
| Fuses          | 3.42       |
| Sling          | 4.49       |
| .5 ton anvil   | 5.99       |
| Oil can        | 8.99       |
| 1 ton anvil    | 9.99       |
| Bird seed      | 10.00      |
| TNT (5 sticks) | 10.00      |
| Detonator      | 13.00      |
| 2 ton anvil    | 14.99      |
| 3 ton anvil    | 19.99      |
| JetPack 1000   | 35.00      |
| Safe           | 50.00      |
| JetPack 2000   | 55.00      |
+----------------+------------+
15 rows in set (0.10 sec)

2、多个字段的排序

mysql> select prod_name, prod_price from products order by prod_price, prod_name;
+----------------+------------+
| prod_name      | prod_price |
+----------------+------------+
| Carrots        | 2.50       |
| TNT (1 stick)  | 2.50       |
| Fuses          | 3.42       |
| Sling          | 4.49       |
| .5 ton anvil   | 5.99       |
| Oil can        | 8.99       |
| 1 ton anvil    | 9.99       |
| Bird seed      | 10.00      |
| TNT (5 sticks) | 10.00      |
| Detonator      | 13.00      |
| 2 ton anvil    | 14.99      |
| 3 ton anvil    | 19.99      |
| JetPack 1000   | 35.00      |
| Safe           | 50.00      |
| JetPack 2000   | 55.00      |
+----------------+------------+
15 rows in set (0.10 sec)

3、当查询多个字段的时候，如果部分信息内容一致，建议增加多组排序。
4、找出最贵或者最便宜的产品； order by 与 （desc）limit 连用。

mysql> select prod_name, prod_price from products order by prod_price, prod_name limit 1;
+-----------+------------+
| prod_name | prod_price |
+-----------+------------+
| Carrots   | 2.50       |
+-----------+------------+
1 row in set (0.07 sec)