Oracle CTEで再帰クエリをリファクタリングしようとしていますか？

書き直そうと思います：

with MyCTE3 (WorkflowStepName, Depth, WorkflowId, WorkflowStepId, SubWorkflowBaseId, SubWorkflowId, Sequence, StepType, JoinColumn, DisplayOrder) as 
(
    SELECT wfs.WorkflowStepName
           ,1 as Depth
           , wfs.WorkflowId
           , wfs.WorkflowStepId
           , wfs.SubWorkflowBaseId
           , wfs.SubWorkflowId
           , wfs.Sequence
           , wfs.StepType
           , case 
                when wfs.SubWorkflowBaseId = '0000000000000000' then wfs.SubworkflowId
                --when wfs.SubWorkflowBaseId is null then wfs.SubworkflowId
                when wfs.SubWorkflowId = '0000000000000000' then wfs.SubWorkflowBaseId
                --when wfs.SubWorkflowId is null then wfs.SubWorkflowBaseId
             end as JoinColumn
          ,1 || '.' || CAST(wfs.Sequence AS VARCHAR(255))  AS DisplayOrder
      --, to_clob(wfs.WorkflowId) as ProcessedWorkflow
      FROM WorkflowStep2 wfs, Workflow2  wf 
     WHERE wfs.WorkflowId = '1100000000000000' 
     and wf.WorkflowId = wfs.WorkflowId

    union all
    SELECT wfs.WorkflowStepName
            ,  Depth+1
            , wfs.WorkflowId
            , wfs.WorkflowStepId
            , wfs.SubWorkflowBaseId
            , wfs.SubWorkflowId
            , wfs.Sequence
            , wfs.StepType
            , case 
                when wfs.SubWorkflowBaseId = '0000000000000000' then wfs.SubworkflowId
                --when wfs.SubWorkflowBaseId is null then wfs.SubworkflowId
                when wfs.SubWorkflowId = '0000000000000000' then wfs.SubWorkflowBaseId
                --when wfs.SubWorkflowId is null then wfs.SubWorkflowBaseId
                end as JoinColumn
        ,DisplayOrder || '.' || CAST(Depth+1 AS VARCHAR(255)) || CAST(wfs.Sequence AS VARCHAR(255))  as DisplayOrder
        --,to_clob(myCTE3.ProcessedWorkflow) || ',' || to_clob(wfs.WorkflowId) as ProcessedWorkflow
        FROM workflowbase2 wfb, workflowstep2 wfs, workflow2 wf, MyCTE3     
    where  myCTE3.JoinColumn is not null
    -- and (','+to_clob(myCTE3.ProcessedWorkflow) +',' not like '%,'+to_clob(wfs.WorkflowId)+',%')    
    -- and (dbms_lob.instr(myCTE3.ProcessedWorkflow,wfs.WorkflowId) = 0)  
        AND
        (    
            myCTE3.SubWorkflowBaseId <>  '0000000000000000' 
            and myCTE3.SubWorkflowBaseId is not null 
            and myCTE3.JoinColumn = wfb.WorkflowBaseId
            and wfb.RevOfRcdId    = wf.WorkflowId
            and wf.workflowid     = wfs.WorkflowId
        )   
), mcte2(WorkflowStepName, Depth, WorkflowId, WorkflowStepId, SubWorkflowBaseId, SubWorkflowId, Sequence, StepType, JoinColumn, DisplayOrder) AS (
  SELECT wfs.WorkflowStepName
           ,1 as Depth
           , wfs.WorkflowId
           , wfs.WorkflowStepId
           , wfs.SubWorkflowBaseId
           , wfs.SubWorkflowId
           , wfs.Sequence
           , wfs.StepType
           , case 
                when wfs.SubWorkflowBaseId = '0000000000000000' then wfs.SubworkflowId
                --when wfs.SubWorkflowBaseId is null then wfs.SubworkflowId
                when wfs.SubWorkflowId = '0000000000000000' then wfs.SubWorkflowBaseId
                --when wfs.SubWorkflowId is null then wfs.SubWorkflowBaseId
             end as JoinColumn
          ,1 || '.' || CAST(wfs.Sequence AS VARCHAR(255))  AS DisplayOrder
      --, to_clob(wfs.WorkflowId) as ProcessedWorkflow
      FROM WorkflowStep2 wfs, Workflow2  wf 
     WHERE wfs.WorkflowId = '1100000000000000' 
     and wf.WorkflowId = wfs.WorkflowId

    union all


  SELECT wfs.WorkflowStepName
            ,  Depth+1
            , wfs.WorkflowId
            , wfs.WorkflowStepId
            , wfs.SubWorkflowBaseId
            , wfs.SubWorkflowId
            , wfs.Sequence
            , wfs.StepType
            , case 
                when wfs.SubWorkflowBaseId = '0000000000000000' then wfs.SubworkflowId
                --when wfs.SubWorkflowBaseId is null then wfs.SubworkflowId
                when wfs.SubWorkflowId = '0000000000000000' then wfs.SubWorkflowBaseId
                --when wfs.SubWorkflowId is null then wfs.SubWorkflowBaseId
                end as JoinColumn
        ,DisplayOrder || '.' || CAST(Depth+1 AS VARCHAR(255)) || CAST(wfs.Sequence AS VARCHAR(255))  as DisplayOrder
        --,to_clob(myCTE3.ProcessedWorkflow) || ',' || to_clob(wfs.WorkflowId) as ProcessedWorkflow
        FROM workflowbase2 wfb, workflowstep2 wfs, workflow2 wf, MyCTE3     
    where  myCTE3.JoinColumn is not null
       AND
        (
            myCTE3.SubWorkflowId <>  '0000000000000000'
            and myCTE3.SubWorkflowId is not null 
            and myCTE3.JoinColumn =  wf.workflowid 
            --and wf.workflowid     = wfs.SubWorkflowId
            and wf.workflowid     = wfs.WorkflowId
      and wf.WorkflowBaseId = wfb.WorkflowBaseId     
        ) 
)
select   WorkFlowStepName, DisplayOrder --, DisplayOrder, ProcessedWorkflow
  from MyCTE3
where MYCTE3.StepType <> 2
UNION ALL
select   WorkFlowStepName, DisplayOrder --, DisplayOrder, ProcessedWorkflow
  from MyCTE3
where MYCTE3.StepType <> 2
order by DisplayOrder ;

SQLFiddleデモ

または拡張 を使用しました