[php][pdo]顯示錯誤訊息 errorCode() 及 errorInfo()

errorCode() 及 errorInfo()
errorCode():

$sth = $dbh->prepare('select * from product where id = :id');
$sth->bindParam(':id',$_POST['id']);
$sth->execute();
if ($sth->errorCode())
{
    echo "恩丟唷~";
    print_r($sth->errorInfo());
}

errorInfo(): 

$sth->errorInfo是一個陣列，有三個索引值分別對應不同訊息
0->SQLSTATE error code
1->返回Drier的錯誤碼
2->返回Driver的錯誤訊息