sql order by——迹忆客-ag捕鱼王app官网

sql order by语句用于根据一列或多列按升序或降序对数据进行排序。某些数据库默认按升序对查询结果进行排序。

语法

order by 语句的基本语法如下

select column-list 
from table_name 
[where condition] 
[order by column1, column2, .. columnn] [asc | desc];

可以在 order by 后面指定多个列，使用逗号隔开。确保用来对该列进行排序的任何列都应该在查询列中。

示例

customers 表

 ---- ---------- ----- ----------- ---------- 
| id | name     | age | address   | salary   |
 ---- ---------- ----- ----------- ---------- 
|  1 | ramesh   |  32 | ahmedabad |  2000.00 |
|  2 | khilan   |  25 | delhi     |  1500.00 |
|  3 | kaushik  |  23 | kota      |  2000.00 |
|  4 | chaitali |  25 | mumbai    |  6500.00 |
|  5 | hardik   |  27 | bhopal    |  8500.00 |
|  6 | komal    |  22 | mp        |  4500.00 |
|  7 | muffy    |  24 | indore    | 10000.00 |
 ---- ---------- ----- ----------- ---------- 

以下代码将按 name 和 salary 按升序对结果进行排序

sql> select * from customers
   order by name, salary;

结果如下

 ---- ---------- ----- ----------- ---------- 
| id | name     | age | address   | salary   |
 ---- ---------- ----- ----------- ---------- 
|  4 | chaitali |  25 | mumbai    |  6500.00 |
|  5 | hardik   |  27 | bhopal    |  8500.00 |
|  3 | kaushik  |  23 | kota      |  2000.00 |
|  2 | khilan   |  25 | delhi     |  1500.00 |
|  6 | komal    |  22 | mp        |  4500.00 |
|  7 | muffy    |  24 | indore    | 10000.00 |
|  1 | ramesh   |  32 | ahmedabad |  2000.00 |
 ---- ---------- ----- ----------- ---------- 

下面的代码将按 name 按降序对结果进行排序。

sql> select * from customers
   order by name desc;

结果如下

 ---- ---------- ----- ----------- ---------- 
| id | name     | age | address   | salary   |
 ---- ---------- ----- ----------- ---------- 
|  1 | ramesh   |  32 | ahmedabad |  2000.00 |
|  7 | muffy    |  24 | indore    | 10000.00 |
|  6 | komal    |  22 | mp        |  4500.00 |
|  2 | khilan   |  25 | delhi     |  1500.00 |
|  3 | kaushik  |  23 | kota      |  2000.00 |
|  5 | hardik   |  27 | bhopal    |  8500.00 |
|  4 | chaitali |  25 | mumbai    |  6500.00 |
 ---- ---------- ----- ----------- ----------