Mysql默认情况下不区分大小写，请尝试将语言排序规则更改为latin1_general_cs

不使用=运算符，您可能希望使用LIKE或LIKE二进制

// this returns 1 (true)
select 'A' like 'a'

// this returns 0 (false)
select 'A' like binary 'a'


select * from user where username like binary 'a'

在它的条件下，它会取a和不取a

Mysql默认情况下不区分大小写，请尝试将语言排序规则更改为latin1_general_cs

对于那些希望使用RLIKE或REGEXP与正则表达式进行区分大小写的比较的人来说，你可以使用REGEXP_LIKE()来匹配匹配类型c，如下所示:

SELECT * FROM `table` WHERE REGEXP_LIKE(`column`, 'value', 'c');

您可以像这样使用二进制区分大小写

select * from tb_app where BINARY android_package='com.Mtime';

不幸的是，此SQL不能使用索引，依赖于该索引的查询将遭受性能损失

mysql> explain select * from tb_app where BINARY android_package='com.Mtime';
+----+-------------+--------+------------+------+---------------+------+---------+------+---------+----------+-------------+
| id | select_type | table  | partitions | type | possible_keys | key  | key_len | ref  | rows    | filtered | Extra       |
+----+-------------+--------+------------+------+---------------+------+---------+------+---------+----------+-------------+
|  1 | SIMPLE      | tb_app | NULL       | ALL  | NULL          | NULL | NULL    | NULL | 1590351 |   100.00 | Using where |
+----+-------------+--------+------------+------+---------------+------+---------+------+---------+----------+-------------+

幸运的是，我有一些技巧来解决这个问题

mysql> explain select * from tb_app where android_package='com.Mtime' and BINARY android_package='com.Mtime';
+----+-------------+--------+------------+------+---------------------------+---------------------------+---------+-------+------+----------+-----------------------+
| id | select_type | table  | partitions | type | possible_keys             | key                       | key_len | ref   | rows | filtered | Extra                 |
+----+-------------+--------+------------+------+---------------------------+---------------------------+---------+-------+------+----------+-----------------------+
|  1 | SIMPLE      | tb_app | NULL       | ref  | idx_android_pkg           | idx_android_pkg           | 771     | const |    1 |   100.00 | Using index condition |
+----+-------------+--------+------------+------+---------------------------+---------------------------+---------+-------+------+----------+-----------------------+  

下面是MySQL版本等于或高于5.5的情况。

添加到/etc/mysql/my.cnf

  [mysqld]
  ...
  character-set-server=utf8
  collation-server=utf8_bin
  ...

我尝试的所有其他排序似乎都不区分大小写，只有“utf8_bin”有效。

在这之后不要忘记重新启动mysql:

   sudo service mysql restart

根据http://dev.mysql.com/doc/refman/5.0/en/case-sensitivity.html，还有一个“latin1_bin”。

“utf8_general_cs”不被mysql启动接受。(我把“_cs”读成“区分大小写”- ??)