PHP Retrieiving Column Data from database - php

Question

I have an earlier post here
But NONE of those answers worked. So here's my entire class code:
<?php
session_start();
class Mysql {
private $conn;
function __construct() {
$this->conn = new PDO('mysql:host=***;dbname=***;charset=UTF-8','***','***') or
die('There was a problem connecting to the database.');
}
function verify_Username_and_Pass($un, $pwd) {
$query = "SELECT Username
FROM Conference
WHERE Username = :un AND Password = :pwd";
$stmt = $this->conn->prepare($query);
$stmt->bindParam(':un', $un);
$stmt->bindParam(':pwd', $pwd);
$stmt->execute();
if ($stmt->rowCount() > 0) {
// User exist
$stmt->bindColumn('First Name', $firstName);
$_SESSION["FirstName"] = $firstName;
die($_SESSION["FirstName"]);
return true;
$stmt->close();
}
else {
// User doesn't exist
//die("failure");
return false;
$stmt->close();
}
}
}
?>
I've tried fetch, i've tried bind_result, etc and none of them print the correct value on the die statement. Now this worked when i stored username in session and tried to print that. What is wrong with the code?

Answer 1

You aren't calling the code in the snippet. What's the call procedure?
You aren't retrieving Conference.First Name only Conference.Username so you should be getting a warning unless you're not displaying errors. You probably want
"SELECT * FROM Conference...."
or
"SELECT FirstName From Conference WHERE Username = :un AND Password = :pwd";
It's possibly Conference.FirstName.
die(); is not very useful for debugging. Try var_dump($_SESSION["FirstName"]); die();

Answer 2

I have looked at your code, and made a working version on my own server. If you have any questions, feel free to ask.
class Mysql
{
private $conn;
public $error;
public $username;
function __construct()
{
try {
$this->conn = new PDO( 'mysql:host=localhost;dbname=****', 'root', '****' );
$this->conn->setAttribute( PDO::ATTR_EMULATE_PREPARES, false );
}
catch ( Exception $e ) {
$this->error = $e->getMessage();
}
}
function verify_Username_and_Pass( $un, $pwd )
{
$query = "SELECT Username
FROM Conference
WHERE Username = :un AND Password = :pwd";
$stmt = $this->conn->prepare( $query );
if( !$stmt ) {
$this->error = $this->conn->errorInfo();
return false;
}
$stmt->bindParam( ':un', $un );
$stmt->bindParam( ':pwd', $pwd );
$stmt->execute();
if ( $stmt->rowCount() > 0 ) {
// User exist
$this->username = $stmt->fetchColumn();
return true;
}
else {
// User doesn't exist
return false;
}
}
}
session_start();
$db = new Mysql();
if( !$db->error ) {
if( $db->verify_Username_and_Pass ( 'user', 'test' )) {
$_SESSION["FirstName"] = $db->username;
}
else
echo 'Unknown user';
}
var_dump( $db );
The script will output this:
Unknown user
object(Mysql)#1 (3) {
["conn":"Mysql":private]=> object(PDO)#2 (0) { }
["error"]=> array(3)
{ [0]=> string(5) "42S02"
[1]=> int(1146)
[2]=> string(39) "Table 'xxxx.Conference' doesn't exist" }
["username"]=> NULL }