trySelect T1.RecordID, T1.ParentID, (Case T1.ParentID When 0 Then T1.ProjectName Else T2.ProjectName End) As ProjectName From A T1 Inner Join A T2 On T1.ParentID = T2.RecordID
為0的節點在數據庫中應該不存在,好象這樣也可以Select T1.RecordID, T1.ParentID, IsNull(T2.ProjectName, T1.ProjectName) As ProjectName From A T1 Inner Join A T2 On T1.ParentID = T2.RecordID
谢谢,可还是不包括,partentID是0的,on给过滤掉了
不好意思,寫錯了,用Left JoinSelect T1.RecordID, T1.ParentID, IsNull(T2.ProjectName, T1.ProjectName) As ProjectName From A T1 Left Join A T2 On T1.ParentID = T2.RecordID
谢谢楼上耐心的写的了这么多遍! SELECT T1.RFMProjectID, T1.ParentID, (CASE T1.ParentID WHEN 0 THEN T1.ProjectName ELSE T2.ProjectName END) AS ProjectName FROM RFMProject T1 LEFT OUTER JOIN RFMProject T2 ON T1.ParentID = T2.RFMProjectID
RecordID,
(Case ParentID When 0 Then RecordID Else ParentID End) As ParentID
From A
T1.RecordID,
T1.ParentID,
(Case T1.ParentID When 0 Then T1.ProjectName Else T2.ProjectName End) As ProjectName
From
A T1
Inner Join
A T2
On T1.ParentID = T2.RecordID
T1.RecordID,
T1.ParentID,
IsNull(T2.ProjectName, T1.ProjectName) As ProjectName
From
A T1
Inner Join
A T2
On T1.ParentID = T2.RecordID
T1.RecordID,
T1.ParentID,
IsNull(T2.ProjectName, T1.ProjectName) As ProjectName
From
A T1
Left Join
A T2
On T1.ParentID = T2.RecordID
SELECT T1.RFMProjectID, T1.ParentID,
(CASE T1.ParentID WHEN 0 THEN T1.ProjectName ELSE T2.ProjectName END)
AS ProjectName
FROM RFMProject T1 LEFT OUTER JOIN
RFMProject T2 ON T1.ParentID = T2.RFMProjectID