树形结构:

SELECT FROMNODEID, TONODEID, FROM_PO,
NVL ((SELECT MANDATORY
FROM TFOPOLICY TFO
WHERE TFO.FACTORYNAME = 'R1'
AND TFO.PROCESSOPERATIONNAME = R.FROM_PO
AND TFO.PROCESSOPERATIONVERSION = '00001'),
'Y'
) AS MANDATORY,
SEQ, ARCTYPE
FROM ( SELECT FROMNODEID, TONODEID, ARCTYPE,
(SELECT NODEATTRIBUTE1
FROM NODE N
WHERE A.FROMNODEID = N.NODEID
AND N.NODETYPE = 'ProcessOperation') AS FROM_PO,
(SELECT NODEATTRIBUTE1
FROM NODE N
WHERE A.TONODEID = N.NODEID
AND N.NODETYPE = 'ProcessOperation') AS TO_PO,
ROWNUM AS SEQ
FROM ARC A
CONNECT BY PRIOR TONODEID = FROMNODEID
AND ( (ARCTYPE = 'Normal')
OR (ARCTYPE = 'Rework' AND ARCATTRIBUTE <> 'Y')
OR (ARCTYPE = 'Conditional' AND ARCATTRIBUTE <> 'Y')
)
START WITH FROMNODEID =
(SELECT NODEID
FROM NODE
WHERE PROCESSFLOWNAME = 'TNFM32'
AND NODETYPE = 'Start')
) R
WHERE R.ARCTYPE = 'Normal' AND R.FROM_PO IS NOT NULL
ORDER BY SEQ;