master controller and m_master(model)

m_master.php

<?php
    class M_Master extends CI_Model
    {
        public function findURI( $uri )
        {
            $query = $this->db->where( 'uri', $uri )->limit(1)->get('pages');
             
            if ( $query->num_rows > 0 )
            {
                echo '<pre>';
                print_r($query->row());
                echo '</pre>';
                return $query->row();
            }
             
            return false;
        }
    } 
?>

master.php

<?php if( !defined('BASEPATH')) exit('No direct script access allowed');
 
    class Master extends CI_Controller
    {
        function __construct()
        {
            parent::__construct();

        }
         
         
        public function _remap( $method )
        {
            // remap overrides function calls
            $this->load->library('single_column'); //put this in here because I don't know what I'm doing
             
		    // search for uri in db
		    $this->load->model('m_master');
		    
		    $uri_id = $this->m_master->findURI( uri_string() );
		             
		    if ( $uri_id != false )
		    {
		        // uri exists! load template controller
		        $this->{$uri_id->controller}->render( $uri_id->id ); //possibly incorrect placment
		    }
		    else
		    {
		        show_404( uri_string() );
		    }
        }
    } 
?>