вот мои пока неудачные попытки :
SELECT * FROM dobjlink_dbt
WHERE t_objecttype = 3 AND t_attrtype = 3
AND t_attrid = 1010204
AND t_objectid IN
(SELECT t_objectid FROM dobjlink_dbt WHERE t_objecttype = 3 AND t_attrtype = 3
UNION
SELECT t_attrid FROM dobjlink_dbt WHERE t_objecttype = 3 AND t_attrtype = 3)