Как объединить два запроса на выборку из разных баз данных?

Question

Я хочу присоединить XY_OBJECT в XY TABLE к YX OBJECT и получить значения, связанные с YX_OBJECTS в базе данных XY. Кажется, я не могу найти способ сохранить целостность запроса генерации иерархии при получении рабочих данных, относящихся ко всему эквалайзеру в списке, генерируемом иерархией.

SELECT -- GENERATES XY ASSOCIATED TO EQ
    XY_OBJECT AS POSITION,
    XY_PPM AS Work,
    XY_CLASS AS XY_CLASS,
    XY_PERSON AS XY_ASSIGNED,
    XY_SCHEDGRP AS XY_SCHEDULER,
    XY_DUE AS NEXT_DUE,
    XY_DEACTIVE AS DEACTIVED_DATE,
    XY_FREQ AS FREQUENCY,
    XY_PERIODUOM AS FREQ_UOM
    FROM    CAN_XYOBJECTS

(SELECT -- GENERATES EQUIPMENT LIST
        YX_MRC AS X_MRC,
        YX_PARENT AS X_PARENT,
        YX_CODE AS X_CODE,
        YX_DESC AS X_DESC,
        YX_CLASS AS X_CLASS,
        YX_COSTCODE AS X_COSTCODE,
        YX_STATUS AS X_STATUS,
        YX_COMMISS AS X_COMMISS,
        LEVEL
        FROM CAN_YXOBJECTS
     START WITH YX_PARENT IN
             (Select
            YX_CODE AS P_CODE
            From CAN_YXOBJECTS 
            Where YX_DESC Like '%GENDO%'
            AND YX_CLASS Like 'PLENT'
            AND YX_STATUS <> 'Q')
        CONNECT BY PRIOR YX_CODE = YX_PARENT)
        ORDER BY X_PARENT