mysql 查询汉语数据
mysql 查询中文数据
我有张表数据量很大,name字段数据有中文的也有英文的,现在我想查出为中文的那些数据?
------解决方案--------------------
先规范一下说法:
这个"中文"虽然我们平时说意义很明确,不过到了电脑里就不那么清楚了....
utf8里中文汉字是和韩文日文汉字放一起的,统称cjk...其实还包括一些全角的符号...
utf8里汉字基本都在3字节区,有个别4字节的不过都是冷僻字,
同时,3字节区里还有印度字啊什么的...因为你不会用到,也就都不管它们...
所以我们简单化一点, 假设你是要找出所有带"3字节utf8字符"的记录
那么可以用这个
name regexp concat('[',char(0xE0),'-',char(0xEF),'][',char(0x80),'-',char(0xBF),'][',char(0x80),'-',char(0xBF),']')
注意\xXX这样的写法没法在mysql里的正则里直接用,所以要用char和concat....google一下没找到更方便的方法...
另外,不知道你数据里是否有2字节区的字符,(欧洲字符希腊字符拉丁字符等),
如果确定没有....确定!!!
就是说你数据里除了单字节的ascii字符,就是3字节的汉字....
那么可以用一个简单的方法:
char_length(name)!=length(name)
------解决方案--------------------
mysql 的 REGEXP不是很强大, 试试 [^[:alnum:][:cntrl:][:space:]]

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