SQL服務器遞歸查詢更新

Question

我有以下查詢

WITH PersonCTE 
    AS 
    (
    SELECT 
    [ParentId], 
    [Id], 
    [Name], 
    [LastDeleted], 
    [LastRestored], 
    [EntryTime] 
    FROM [dbo].[Backup] 
    WHERE [Id] = someguid 
    UNION ALL 
    SELECT 
    c.ParentId, 
    c.Id, 
    c.Name, 
    c.LastDeleted, 
    c.LastRestored, 
    c.EntryTime 
    FROM [dbo].[Backup] c 
    INNER JOIN PersonCTE s 
    ON c.ParentId = s.Id 
) 
    SELECT * 
    FROM PersonCTE 

需要在事後做這種更新：

UPDATE Backup 
    SET [LastRestored] = GETDATE 

我希望能夠設置LastRestored到GETDATE只受影響的結果的行。

Answer 1

SQL Server允許您運行CTE更新見下面的例子

DECLARE @t TABLE(id INT , today DATE NULL) 

INSERT INTO @t (id,today) 
VALUES(1,NULL),(2,NULL) 

;WITH cte AS 
(
SELECT * FROM @T WHERE today IS NULL 
) 
UPDATE cte SET today = GETDATE() 

SELECT * FROM @t 


-- in your query try this 

WITH PersonCTE 
    AS 
    (
    SELECT 
    [ParentId], 
    [Id], 
    [Name], 
    [LastDeleted], 
    [LastRestored], 
    [EntryTime] 
    FROM [dbo].[Backup] 
    WHERE [Id] = someguid 
    UNION ALL 
    SELECT 
    c.ParentId, 
    c.Id, 
    c.Name, 
    c.LastDeleted, 
    c.LastRestored, 
    c.EntryTime 
    FROM [dbo].[Backup] c 
    INNER JOIN PersonCTE s 
    ON c.ParentId = s.Id 
) 
update PersonCTE 

SET [LastRestored] = GETDATE()