class dbconnect{
        public function connect(){
            $host = 'localhost';
            $user = 'root';
            $pass = '';
            $db = 'demo';
            $connection = mysqli_connect($host,$user,$pass,$db);
            return $connection;
        }
    }

include 'dbconnect.php';
    class dao extends dbconnect{
        private $conn;
        function __dao(){
            $dbcon = new dbconnect();
            $conn = $dbcon->connect();
        }
        function select( $table , $where='' , $other='' ){
            if(!$where = '' ){
                $where = 'where' . $where;
            }
            $sele = mysqli_query($this->conn,"SELECT * FROM  $table $where $other") or die(mysqli_error($this->conn));
            echo $sele;
            return $sele;
        }
    }