CODEWITHSUNDEEP
phppdo
Suraj Shrestha
Suraj Shrestha

Reputation: 1

Retrieving data using PDO connection

I am trying to learn PHP OOP concept and has a database connection using PDO as below:

class db{
private $host;
private $user;
private $pass;
private $dname;
private $conn;

function __construct(){
    $this->host = "localhost";
    $this->user = "root";
    $this->pass = "";
    $this->dname= "nast";
    $this->connect();
}

function __destruct(){
    $this->disconnect();
}

function connect(){

    if(!$this->conn){

        try{
            $this->conn = new PDO('mysql:host='.$this->host.'; dbname='.$this->dname.'', $this->user, $this->pass,
                                  array(PDO::MYSQL_ATTR_INIT_COMMAND => 'SET NAMES utf8'));
        }

        catch(Exception $e){
            die('Erreur:' .$e->getMessage());
        }

        if(!$this->conn){
            $this->status_fatal = true;
            echo'Connection Not Established';   
            die();
        }
        else{
            $this->status_fatal = false;            }
    }
    return $this->conn;
}

function disconnect(){
    if($this->conn){
        $this->conn = null;
    }
}

}

And named it "class.db.php". I got it from internet.

Then I tried to retrieve data from the database using the following code 

require 'class.db.php';

$bdd = new db(); // create a new object, class db()
$sql = 'SELECT * FROM student';

$q = $bdd->query($sql);
$q->setFetchMode(PDO::FETCH_ASSOC);

$r = $q->fetch();
echo $r['id'];

But it give the following error:

Call to undefined method db::query() in C:\xampp\htdocs\prac\class.my.php on line 8.

Upvotes: 0

Views: 85

Answers (1)

Dexter Bengil
Dexter Bengil

Reputation: 6625

As what the error says, the function query() doesn't exist in your db class. Add a query function on your db class, something like this: 

function query($sql){
   $this->connect(); // open a connection

   // do your codes here

   $this->disconnect(); // close the connection
}

Upvotes: 1

Related Questions