/** * return foreign keys and entity references * * @static * @access public * @return array of CRM_Core_EntityReference */ static function getReferenceColumns() { if (!self::$_links) { self::$_links = array(new CRM_Core_EntityReference(self::getTableName(), 'slot_id', 'civicrm_booking_slot', 'id'), new CRM_Core_EntityReference(self::getTableName(), 'resource_id', 'civicrm_booking_resource', 'id'), new CRM_Core_EntityReference(self::getTableName(), 'config_id', 'civicrm_booking_resource_config_option', 'id')); } return self::$_links; }