mysql regexp 中文匹配问题？？？

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SELECT
	'测试好友' REGEXP '[123456789 一二三]',
	'测试好友' REGEXP '[123456789 一二三四]',
	'测试好友' REGEXP '[123456789 一二三五]' 
FROM
	DUAL;

输出为 0, 1, 0，这是为何？中文是按照拼音首字母判断的吗？

上面 REGEXP 里没有空格，保存的时候自动添加的，有没有结果都一样

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https://mariadb.com/kb/en/library/pcre/
```text
Also, REGEXP/RLIKE, and the new functions, now work correctly with all multi-byte character sets supported by MariaDB, including East-Asian character sets (big5, gb2313, gbk, eucjp, eucjpms, cp932, ujis, euckr), and Unicode character sets (utf8, utf8mb4, ucs2, utf16, utf16le, utf32). In earlier versions of MariaDB (and all MySQL versions) REGEXP/RLIKE works correctly only with 8-bit character sets.
```

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https://dev.mysql.com/doc/refman/8.0/en/regexp.html
```text
MySQL implements regular expression support using International Components for Unicode (ICU), which provides full Unicode support and is multibyte safe. (Prior to MySQL 8.0.4, MySQL used Henry Spencer's implementation of regular expressions, which operates in byte-wise fashion and is not multibyte safe. For information about ways in which applications that use regular expressions may be affected by the implementation change, see Regular Expression Compatibility Considerations.)
```

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Starting with MariaDB 10.0.5, MariaDB switched to the PCRE regular expression library for enhanced regular expressions.