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我没有找到类似的问题，可能是因为我没有找到正确的单词（英语不是我的第一语言）

问题

我有一个varchar末尾有空格的值："opt-193-381-markets "当我对没有空格SELECT的值执行 a 时，它返回相同的结果。就像 MySQL 正在修剪中的值WHERE

表定义：

mysql> desc message;
+------------+--------------+------+-----+---------+-------+
| Field      | Type         | Null | Key | Default | Extra |
+------------+--------------+------+-----+---------+-------+
| FileId     | int(11)      | NO   | PRI | 0       |       |
| MessageKey | varchar(100) | NO   | PRI |         |       |
| NumericKey | tinyint(1)   | NO   |     | 0       |       |
| IsObsolete | tinyint(4)   | YES  | MUL | NULL    |       |
| notes      | text         | YES  |     | NULL    |       |
+------------+--------------+------+-----+---------+-------+

例子：

mysql> SELECT * FROM message WHERE MessageKey = "opt-193-381-markets";
+--------+----------------------+------------+------------+-------+
| FileId | MessageKey           | NumericKey | IsObsolete | notes |
+--------+----------------------+------------+------------+-------+
|    304 | opt-193-381-markets  |          0 |          1 | NULL  |
|    337 | opt-193-381-markets  |          0 |          1 | NULL  |
+--------+----------------------+------------+------------+-------+

请注意，MessageKey末尾有空格的值，我只是要求没有空格的值。

mysql> SELECT * FROM message WHERE MessageKey = "opt-193-381-markets ";
+--------+----------------------+------------+------------+-------+
| FileId | MessageKey           | NumericKey | IsObsolete | notes |
+--------+----------------------+------------+------------+-------+
|    304 | opt-193-381-markets  |          0 |          1 | NULL  |
|    337 | opt-193-381-markets  |          0 |          1 | NULL  |
+--------+----------------------+------------+------------+-------+

再增加一个空间

mysql> SELECT * FROM message WHERE MessageKey = "opt-193-381-markets  ";
+--------+----------------------+------------+------------+-------+
| FileId | MessageKey           | NumericKey | IsObsolete | notes |
+--------+----------------------+------------+------------+-------+
|    304 | opt-193-381-markets  |          0 |          1 | NULL  |
|    337 | opt-193-381-markets  |          0 |          1 | NULL  |
+--------+----------------------+------------+------------+-------+

逃离空间

mysql> SELECT * FROM message WHERE MessageKey = "opt-193-381-markets\ \ ";
+--------+----------------------+------------+------------+-------+
| FileId | MessageKey           | NumericKey | IsObsolete | notes |
+--------+----------------------+------------+------------+-------+
|    304 | opt-193-381-markets  |          0 |          1 | NULL  |
|    337 | opt-193-381-markets  |          0 |          1 | NULL  |
+--------+----------------------+------------+------------+-------+

我也试过单引号'opt-193-381-markets'

问题

为什么我无法搜索 的确切值MessageKey？

谢谢

4

1 回答 1

4

使用二元比较运算符。

SELECT * FROM message WHERE BINARY(MessageKey) = 'opt-193-381-markets';

于 2013-11-14T14:13:59.210 回答