/**
  * returns all the column names of this table
  *
  * @access public
  * @return array
  */
 function &fields()
 {
     if (!self::$_fields) {
         self::$_fields = array('id' => array('name' => 'id', 'type' => CRM_Utils_Type::T_INT, 'required' => true), 'activity_id' => array('name' => 'activity_id', 'type' => CRM_Utils_Type::T_INT, 'required' => true, 'FKClassName' => 'CRM_Activity_DAO_Activity'), 'assignee_contact_id' => array('name' => 'assignee_contact_id', 'type' => CRM_Utils_Type::T_INT, 'required' => true, 'FKClassName' => 'CRM_Contact_DAO_Contact'));
     }
     return self::$_fields;
 }