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HomeDatabaseMysql Tutorialmysql中文查询时的字符集匹配问题解决方法

mysql中文查询时的字符集匹配问题解决方法

Jun 07, 2016 pm 04:18 PM
mysqlChinesematchcharacter setmethodInquiresolvequestion

我在写一个查询条件时的问题如下: 如我想写一个字段中包含李字的所有记录 ?$str=李; select * from table where field like ''%?$str%'' ; 显示的记录中除了包含李字的记录,还有不包含李字的记录。为什么? 在MySQL中,进行中文排序和查找的时候,对汉字的

  我在写一个查询条件时的问题如下:

  如我想写一个字段中包含“李”字的所有记录

  ?$str="李";

  select * from table where field like ''%?$str%'' ;

  显示的记录中除了包含”李”字的记录,还有不包含“李”字的记录。为什么?

  在MySQL中,进行中文排序和查找的时候,,对汉字的排序和查找结果是错误的。这种情况在MySQL的很多版本中都存在。如果这个问题不解决,那么MySQL将无法实际处理中文。

  出现这个问题的原因是:MySQL在查询字符串时是大小写不敏感的,在编绎MySQL时一般以ISO-8859字符集作为默认的字符集,因此在比较过程中中文编码字符大小写转换造成了这种现象。

  方法一:

  解决方法是对于包含中文的字段加上"binary"属性,使之作为二进制比较,例如将"name char(10)"改成"name char(10)binary"。

  方法二:

  如果你使用源码编译MySQL,可以编译MySQL时使用--with--charset=gbk 参数,这样MySQL就会直接支持中文查找和排序了。

  方法三:

  可以使用 Mysql 的 locate 函数来判断。以上述问题为例,使用方法为:

  SELECT * FROM table WHERE locate(field,''李'') > 0;

  本站使用的就是这种方法,感觉还不错。:P

  方法四:

  把您的Select语句改成这样,SELECT * FROM TABLE WHERE FIELDS LIKE BINARY ''%FIND%''即可!

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