Question

当变量中存储单个值时，以下工作正常：

Set @var = 121;
select * from table where id = @var;

如何设置具有多个值的变量，然后在查询中使用它。我试过这个，但它不起作用：

set @var = (
  117,120,121,122,143,151,175,233,387,189,118,119,339,357,500,501,493,425,307,191,
  117,120,121,122,143,151,175,233,387,189,118,119,339,357,500,501,493,425,307,191,
  117,120,121,122,143,151,175,233,387,189,118,119,339,357,500,501,493,425,307,191
)
select * from table where id = @var;

Answer 1

set @var = '
  117,120,121,122,143,151,175,233,387,189,118,119,339,357,500,501,493,425,307,191,
  117,120,121,122,143,151,175,233,387,189,118,119,339,357,500,501,493,425,307,191,
  117,120,121,122,143,151,175,233,387,189,118,119,339,357,500,501,493,425,307,191'

SELECT * FROM table WHERE FIND_IN_SET(id,@var);

感谢好友

Answer 2

您可以通过将@var设置为逗号分隔字符串并使用like来获取数据。这不完美但可行，你必须关注@var中的价值。不应该有space

之类的无效字符

Mysql> set @var = '117,120,121,122,143,151,175,233,387,189,118,119,339,357,500,501,493,425,307,191,117,120,121,122,143,151,175,233,12';
Query OK, 0 rows affected (0.00 sec)

Hitesh> select * from test where ((@var like concat(id,',%')) or  (@var like concat('%,',id)) or (@var like concat('%,',id,',%')) or  (@var like id));
+----+------+-------+
| ID | NAME | VALUE |
+----+------+-------+
| 12 | Nee  |  NULL |
+----+------+-------+
1 row in set (0.00 sec)

您也可以使用LOCATE功能代替like。 MySQL LOCATE（）返回字符串中第一次出现字符串的位置。这两个字符串都作为参数传递。可选参数可用于指定将从哪个位置开始搜索（即，要搜索的字符串）搜索。如果未提及此位置，则从头开始搜索。

语法LOCATE(substr,str)

mysql> SELECT LOCATE('st','myteststring'); 
+-----------------------------+
| LOCATE('st','myteststring') |
+-----------------------------+
|                           5 | 
+-----------------------------+

FIND_IN_SET()非常适合您的情况。它must have strin g的值为comma separated。

Answer 3

你应该使用IN

具有多个值的Mysql变量

3 个答案: