/**
  * Check if the if the database needs to be updated
  *
  * @since    0.1.0
  */
 public function check_version()
 {
     global $wpdb;
     $booking_table_name = $wpdb->prefix . Resource_Booking_DB::$booking_table;
     if (get_option('rb_db_version') != Resource_Booking_DB::$rb_db_version || $wpdb->get_var("SHOW TABLES LIKE '{$booking_table_name}'") != $booking_table_name) {
         Resource_Booking_DB::create_tables();
     }
 }