db.php

<?php

$databaseHost = "localhost";
$databaseName = "hackathon";
$databaseUsername = "root";
$databasePassword = "";

try {
    // http://php.net/manual/en/pdo.connections.php
    $dbConn = new PDO("mysql:host={$databaseHost};dbname={$databaseName}", $databaseUsername, $databasePassword);

    $dbConn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); // Setting Error Mode as Exception
    // More on setAttribute: http://php.net/manual/en/pdo.setattribute.php
} catch(PDOException $e) {
    echo $e->getMessage();
}

if ($dbConn){
   echo 'connection to database is done successfully';
}

?>