An uncaught Exception was encountered

Type: Error

Message: Call to a member function result() on boolean

Filename: /var/www/html/application/models/Kategori_staff_model.php

Line Number: 18

Backtrace:

File: /var/www/html/application/controllers/Staff.php
Line: 16
Function: listing

File: /var/www/html/index.php
Line: 315
Function: require_once