PHP连接MySQL的多种方式

mysql_connect模式

$conn = @mysql_connect(DB_HOST,DB_USER,DB_PASSWORD);@mysql_select_db(DB_NAME);$query = "SELECT * FROM grade";$result = @mysql_query($query);print_r(mysql_fetch_array($result,MYSQL_ASSOC));mysql_free_result($result);mysql_close($conn);

PDO模式

$pdo = new PDO("mysql:host=localhost;dbname=test", "root", "");$rs = $pdo -> query("select * from test");while ($row = $rs -> fetch()) {print_r($row["name"]);}

mysqli模式

//1.创建一个mysqli的对象$_mysqli = new mysqli();//2.连接MySQL的主机、用户、密码、数据库$_mysqli->connect('localhost','root','yangfan','guest');//3.创建带连接参数的mysqli对象$_mysqli = new mysqli('localhost','root','yangfan','guest');//4.单独选择数据库$_mysqli->select_db('testguest');//5.断开MySQL$_mysqli->close();