MySQL 如何获得与IN子句中提供的相同顺序的查询结果

你可以使用IN()以及ORDER BY FIELD()来实现。让我们首先创建一个表 –

mysql> create table DemoTable
(
   Id int NOT NULL AUTO_INCREMENT PRIMARY KEY,
   FirstName varchar(100)
);
Query OK, 0 rows affected (0.64 sec)

使用insert命令将一些记录插入该表中 –

mysql> insert into DemoTable(FirstName) values('Chris');
Query OK, 1 row affected (0.19 sec)
mysql> insert into DemoTable(FirstName) values('Robert');
Query OK, 1 row affected (0.08 sec)
mysql> insert into DemoTable(FirstName) values('Mike');
Query OK, 1 row affected (0.13 sec)
mysql> insert into DemoTable(FirstName) values('Sam');
Query OK, 1 row affected (0.12 sec)
mysql> insert into DemoTable(FirstName) values('Carol');
Query OK, 1 row affected (0.10 sec)
mysql> insert into DemoTable(FirstName) values('David');
Query OK, 1 row affected (0.42 sec)

使用select语句显示表中的所有记录 –

mysql> select *from DemoTable;

这将生成以下输出 –

+----+-----------+
| Id | FirstName |
+----+-----------+
|  1 | Chris     |
|  2 | Robert    |
|  3 | Mike      |
|  4 | Sam       |
|  5 | Carol     |
|  6 | David     |
+----+-----------+
6 rows in set (0.00 sec)

以下是如何按照IN子句中提供的顺序获取查询结果的方法。

mysql> select FirstName from DemoTable where Id IN(4,5,6) order by field(Id,4,5,6);

这将生成以下输出 –

+-----------+
| FirstName |
+-----------+
| Sam       |
| Carol     |
| David     |
+-----------+
3 rows in set (0.00 sec)

阅读更多：MySQL 教程