Question

I need to manage hierarchy data storing in my database. But I have a problem now. Please see my example

I have a table called COMMON.TASK_REL

My second table is called Common. task

I suppose need to sort the task_seq and return a result like below:

Task Name        || Task_Seq
    Item1               1
    ..Item1.2           1
    ...Item1.2.1        1
    ..Item1.1           2

Here is my query

--Common task SQL modify --
WITH ctLevel
AS
(
SELECT
   C_TASK_ID AS Child
  ,P_Task_ID AS Parent
  ,common_task.TASK_SEQ AS taskOrder
  ,1 AS [Level]
  ,CAST(C_TASK_ID AS VARCHAR(MAX)) AS [Order]
  ,CAST (Replicate('.', 1) + common_task.TASK_NAME AS VARCHAR(25)) AS [Task_Name]
FROM   
       [COMMON.TASK_REL] as common_task_rel, 
       [COMMON.TASK] as common_task
WHERE common_task_rel.C_TASK_ID = common_task.TASK_ID
    and common_task.[TASK_TYPE] = 'B' AND common_task.[MODULE_CODE] = 'LWRPT' 
    AND common_task.[STATUS] <> 'D'
UNION ALL

SELECT 
   C_TASK_ID AS Child
  ,P_Task_ID AS Parent
  ,common_task.TASK_SEQ AS taskOrder
  ,[Level] + 1 AS [Level]
  ,[Order] + '.' + CAST(C_TASK_ID AS VARCHAR(MAX)) AS [Order]
  ,CAST (Replicate('.', [Level] + 1) + common_task.TASK_NAME AS VARCHAR(25)) AS [Task_Name]
FROM   [COMMON.TASK_REL] as common_task_rel
    INNER JOIN ctLevel
       ON ( P_Task_ID = Child ) , [COMMON.TASK] as common_task
WHERE common_task_rel.C_TASK_ID = common_task.TASK_ID
    and common_task.[TASK_TYPE] = 'B' AND common_task.[MODULE_CODE] = 'LWRPT'
    AND common_task.[STATUS] <> 'D'
)

-- Viewing Data
SELECT Child ,Parent ,taskOrder,Level,[Order],Task_Name
FROM   ctLevel  
GROUP BY Child ,Parent ,taskOrder,Level,[Order],Task_Name
order by [Order];
GO

But my result returns duplicated rows:

Anyone can help me correct my query? Thanks

Answer 1

I believe that your duplicates are coming from your root/anchor query. You should add the following to that query:

AND Task_Seq = 0

Basically, you only want the root to be set up as the beginning of the tree. 301|300 should not be picked up until the recursion section (the part after union all)

If that does not make sense, then I can repaste your query with the modification, but that seemed unnecessary for a small change.