要将字符写入为  UTF-8 使用下面方法

$mysql_mylink = mysql_connect($mysql_host, $mysql_user, $mysql_pass);
mysql_query("SET NAMES 'UTF-8'");
 

数据库字符集为utf-8
mysql_query("SET NAMES 'UTF8'");
mysql_query("SET CHARACTER SET UTF8");
mysql_query("SET CHARACTER_SET_RESULTS=UTF8'");

$db->query("SET NAMES UTF8");