学习PHP PDO ..想知道在涉及多个查询时使用它的正确方法

class connectDB
{
public $db_host = "asdf.db.asdf.hostedresource.com";
public $db_name = "asdf";
public $db_user = "asdf";
public $db_pass = "asdf!1";
public $result;

function setDB_Host($value){
 $this->db_host=$value;
}

function setDB_name($value){
 $this->db_name=$value;
}

 function setDB_user($value){
 $this->db_user=$value;
}

function setDB_pass($value){
 $this->db_pass=$value;
}

function makeConnection()
{
    $connection = mysql_connect($this->db_host,$this->db_user,$this->db_pass) or die
    ("Unable to connect!");
    mysql_select_db($this->db_name) or die(mysql_error());
}

function setQuery($query)
{
    $this->result = mysql_query($query) or die(mysql_error());
}


    class video
    {
       public $sequence;
       public $fileName;
       public $vidTitle;
       public $vidCat;
       public $thumbName;


function addVideo($sequence,$fileName,$vidTitle,$vidCat,$thumbName)
{
    $this->connect-> setQuery("SELECT COUNT(id) AS numrows FROM vids WHERE vidCat = '$vidCat'");
    $row = mysql_fetch_array($this->connect->result);
    $sequence = $row['numrows'] + 1;
    $this->connect->setQuery("INSERT INTO vids (sequence,fileName,vidTitle,vidCat,thumbName) VALUES ('$sequence','$fileName','$vidTitle','$vidCat','$thumbName') ");

}

    function addKeypoints($keypoints,$mins,$secs)
{
        $v_id = mysql_insert_id();

    for ($i=0; $i<sizeof($keypoints); $i++)
    {       
        $totalsecs = ($mins[$i]*60) + $secs[$i];
        $this->connect->setQuery("INSERT INTO keypoints (v_id,totalsecs,keypoints,mins,secs) VALUES ('$v_id','$totalsecs','$keypoints[$i]','$mins[$i]','$secs[$i]') ");
    }

}

不想读所有这些.基本上我只是运行一堆访问我的第一个类的方法,并运行查询.我不明白这在PDO环境中是如何工作的. PDO应该让这种事情变得更容易,因为它是基于OOP的……正确吗？

$hostname = "aaa.db.7149468.aaa.com";
    $username = "coolcaaaaodez";
    $password = "aaaa";

    try
    {
$dbh = new PDO("mysql:host=$hostname;dbname=coolcodez",$username,$password);
$dbh->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);

$stmt = $dbh->prepare("INSERT INTO links (link,cool,difficulty) values (:link,:cool,:difficulty)");

$stmt->bindParam(':link',$_POST['link']);
$stmt->bindParam(':cool',$_POST['cool']);
$stmt->bindParam(':difficulty',$_POST['difficulty']);

if(isset($_POST['submit-links']))
{
    $stmt->execute();
    echo "row added <br />";
}
    }
   catch(PDOException $e)
   {
        echo $e->getMessage();
   }

基本上我要问的是..尝试/捕捉的东西真的让我感到高兴.是否只需将连接本身放入try / catch块中,然后我可以在属于某个类的每个方法中准备查询？或者每个事件序列(数据库连接,查询,结果等)都需要卡在try / catch块中. PDO对我的需求有点花哨,但我正在努力学习,并且我想知道在涉及大量查询时编写它的最佳通用方法.