如何按IN子句的顺序选择MySQL行？

您需要使用FIND_IN_SET()函数按照IN子句的顺序选择MySQL行。语法如下：

SELECT yourVariableName.*
FROM yourTableName yourVariableName
WHERE yourVariableName.yourColumnName IN(value1,value2,...N)
ORDER BY FIND_IN_SET( yourVariableName.yourColumnName,'value1,value2,...N');

为了理解上述语法，让我们创建一个表。创建表的查询如下所示 −

mysql> create table InDemo
   -> (
   -> CodeId int,
   -> Name varchar(20)
   -> );
Query OK, 0 rows affected (0.95 sec)

使用insert命令在表中插入一些记录。查询如下所示−

mysql> insert into InDemo values(1,'John');
Query OK, 1 row affected (0.24 sec)
mysql> insert into InDemo values(2,'Carol');
Query OK, 1 row affected (0.19 sec)
mysql> insert into InDemo values(3,'Sam');
Query OK, 1 row affected (0.18 sec)
mysql> insert into InDemo values(4,'Bob');
Query OK, 1 row affected (0.17 sec)

现在，您可以使用select语句从表中显示所有记录。查询如下所示−

mysql> select *from InDemo;

输出如下所示−

+--------+-------+
| CodeId | Name  |
+--------+-------+
|      1 | John  |
|      2 | Carol |
|      3 | Sam   |
|      4 | Bob   |
+--------+-------+
4 rows in set (0.00 sec)

以下是按IN子句的顺序选择MySQL行的查询语句−

mysql> select tbl.*
   -> from InDemo tbl
   -> where tbl.CodeId in(1,3,2,4)
   -> ORDER BY FIND_IN_SET( tbl.CodeId,'1,3,2,4');

输出如下所示−

+--------+-------+
| CodeId | Name  |
+--------+-------+
|      1 | John  |
|      3 | Sam   |
|      2 | Carol |
|      4 | Bob   |
+--------+-------+
4 rows in set (0.00 sec)

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