PHP-PDOのmysql基礎操作

<?php

    /* pdo    */

    $dsn    = 'mysql:host=localhost;dbname=cswl';//    dsn

    $db     = new pdo($dsn,'root','');//   pdo【         ，      】

    #.  

    $obj    = $db->prepare("show tables;");//     sql  

    $obj->execute();//       

    $obj->fetchALL(PDO::FETCH_ASSOC);//     

    #.  

    $obj    = null;

    $sql    = "insert into level_class 

              (sales_id,levelName,gameName,addTime,status) VALUES (?,?,?,?,?)";

    $obj    = $db->prepare($sql);//     sql  

    $obj->execute(array(1,'  ','  ',time(),1));//        

    #.  

    $obj    = null;

    $sql    = "delete from level_class";

    $obj    = $db->prepare($sql);

    $obj->execute();

?>