public function SetCategoryPermissionIDs() {
      // First build a list of category
      $Permissions = $this->SQL->GetWhere('Permission', array('JunctionColumn' => 'PermissionCategoryID', 'JunctionID >' => 0))->ResultArray();
      $CategoryIDs = array();
      foreach ($Permissions as $Row) {
         $CategoryIDs[$Row['JunctionID']] = $Row['JunctionID'];
      }
      
      // Update all of the child categories.
      $Root = CategoryModel::Categories(-1);
      $this->_SetCategoryPermissionIDs($Root, $Root['CategoryID'], $CategoryIDs);
   }