//数据库连接
define('DB_HOST','localhost');
define('DB_USER','root');
define('DB_PWD','root');
define('DB_NAME','rsp_hts');
//创建数据库连接
$_conn = @mysql_connect(DB_HOST,DB_USER,DB_PWD) or die('数据里连接失败');
//选择一款数据库
mysql_select_db(DB_NAME) or die('指定的数据库不存在');
//选择字符集
mysql_query('SET NAMES UTF8') or die('字符集错误');
//执行一条sql语句
mysql_query("SELECT tg_username FROM tg_user WHERE tg_username='{$_clean['username']}'") or die('SQL错误');
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