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HomeDatabaseMysql TutorialMySQL插入数据的编码过程

找到这篇文章,里面提到从latin1到UTF8的MySQL编码转换。收藏一下,最近要将所有的数据库都转一次,一直错误的使用latin1,再不转

找到这篇文章,里面提到从latin1到UTF8的MySQL编码转换。收藏一下,最近要将所有的数据库都转一次,一直错误的使用latin1,再不转以后麻烦大了。

SET character_set_client='utf8'

SET character_set_connection='utf8'

SET character_set_results='utf8'

在MySQL4.1以后引入字符集后,他定义字符集通过5个方式来匹配,分别是:服务器环境所用的字符集,数据库,表或者字段所用的字符集,数据库连接用的字符集,,数据库返回结果用的字符集和客户端用的字符集
MySQL 默认都是latin1语言,非常奇怪的事。所以如果你要查询某个库,如果不特殊指定,那么MySQL将按照如下方式:客户端用latin1发送查询信息,通过latin1和数据库建立连接,查询后再用latin1语返回结果,那么当然我们在简体中文浏览器里面看到是乱码了。无论你在建立数据库得时候定义库是什么字符,表是什么字符集去存储都一样。
所以如果要正确得到插入,查询结果,简单的方法是在连接数据库成功后,在查询操作前先$sql = "SET NAMES 'gb2312';
mysql_query($sql);这样将当前数据库连接字符集改为gb2312,这样就没有问题了。


出处:未知

个人建议,数据库字符集尽量使用utf8(utf-8),以使你的数据能很顺利的实现迁移,因为utf8字符集是目前最适合于实现多种不同字符集之间的转换的字符集,尽管你在命令行工具上无法正确查看数据库中的内容,我依然强烈建议使用utf8作为默认字符集.
接下来是完整的一个例子:
1.创建数据库表

mysql>CREATE DATABASE IF NOT EXISTS my_db default charset utf8 COLLATE utf8_general_ci;
#注意后面这句话 “COLLATE utf8_general_ci“,大致意思是在排序时根据utf8编码格式来排序
#那么在这个数据库下创建的所有数据表的默认字符集都会是utf8了

mysql>create table my_table (name varchar(20) not null default '')type=myisam default charset utf8;
#这句话就是创建一个表了,制定默认字符集为utf8

2.写数据
通过php直接插入数据:


通过页面提交插入数据:

mysql_connect('localhost','user','password'); mysql_select_db('my_db');
if(isset($_REQUEST['name')) { //由于上面已经指定本页字符集为utf-8了,因此无需转换编码 mysql_query(sprintf("insert into my_table values('%s');", $_REQUEST['name'])); }
$q = mysql_query("select * from my_table"); while($r = mysql_fetch_row($q)) { print_r($r); } ?>


自此,使用utf8字符集的完整的例子结束了.
如果你想使用gb2312编码,那么建议你使用latin1作为数据表的默认字符集,这样就能直接用中文在命令行工具中插入数据,并且可以直接显示出来.而不要使用gb2312或者gbk等字符集,如果担心查询排序等问题,可以使用binary属性约束,例如:

create table my_table ( name varchar(20) binary not null default '')type=myisam default charset latin1;
附:旧数据升级办法
以原来的字符集为latin1为例,升级成为utf8的字符集。原来的表: old_table (default charset=latin1),新表:new_table(default charset=utf8)。
第一步:导出旧数据

mysqldump --default-character-set=latin1 -hlocalhost -uroot -B my_db --tables old_table > old.sql
第二步:转换编码

iconv -t utf-8 -f gb2312 -c old.sql > new.sql
在这里,假定原来的数据默认是gb2312编码。
第三步:导入
修改old.sql,增加一条sql语句: “SET NAMES utf8;“,保存。

mysql -hlocalhost -uroot my_db 大功告成!

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