SQL查詢爲父子關係

Question

我有分貝表作爲父子關係：

NodeId NodeName ParentId 
------------------------------ 
1   Node1  0 
2   Node2  0 
3   Node3  1 
4   Node4  1 
5   Node5  3 
6   Node6  5 
7   Node7  2 

這裏的parentId = 0意味着它是一個根級別節點。現在我想編寫一個SQL查詢，它將返回父類別的所有級別的子級。

例如爲節點ID = 1，它應該返回3，4，5，6

我使用MS SQL Server 2005的

Answer 1

with [CTE] as (
    select * from [TheTable] c where c.[ParentId] = 1 
    union all 
    select * from [CTE] p, [TheTable] c where c.[ParentId] = p.[NodeId] 
) 
select * from [CTE] 

Answer 2

你應該看看使用嵌套集合模型內的父子關係SQL數據庫。這比試圖像這樣在表中存儲記錄的parentID好得多，並且使得這樣的查詢更容易。

Answer 3

而只是爲了確保它正常工作，如果其自身的父（否則它會重複，直到它打破）：

with [CTE] as (
     select * from [TheTable] c where c.[ParentId] = 1 
     union all 
     select * from [CTE] p, [TheTable] c where c.[ParentId] = p.[NodeId] 
     and c.[ParentId] <> c.[NodeId] 
    ) 
    select * from [CTE] 

Answer 4

WITH Temp_Menu AS 
( 
    SELECT AM.* from FCB_AccessMenu AM where AM.[ParentId] = 6 

      UNION ALL  

     SELECT AM.* FROM FCB_AccessMenu AM ,Temp_Menu TM WHERE AM.[ParentID]=TM.[MenuID]   

) 

    SELECT * FROM Temp_Menu ORDER BY ParentID