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TSQL Parent>Child>Sub-Child复制(无光标)

fast-forward cursors tsql sql-server

Matthew · 技术社区 · 14 年前

我正在创建一个SQL2008R2存储过程来复制一行及其所有子行。

这是一个包含父级、子级和子级的三层设置给定父级的ID,我需要创建一个副本。

我已经用一个 fast_forward cursor .

有没有更好的方法来完成这个任务而不使用光标?

TBLACStages可能有1到20个对应行(TBLACUpgrade可能每个TBLACStages行有3行)

CREATE PROCEDURE [dbo].[spDuplicateACUnit]
@pACUnitID bigint = 0 
AS BEGIN
SET NOCOUNT ON;

DECLARE @NewACUnitID bigint = 0

INSERT INTO TBLACUnits ([col1] ,[col2] ,[...] ,[coln]) SELECT [col1] ,[col2] ,[...] ,[coln] FROM TBLACUnits WHERE ACUnitID = @pACUnitID

SELECT @NewACUnitID = SCOPE_IDENTITY()

DECLARE @ACStageID bigint = 0 
    DECLARE @NewACStageID bigint = 0

DECLARE @ACUnitCursor CURSOR

SET @ACUnitCursor = CURSOR LOCAL FAST_FORWARD FOR SELECT ACStageID FROM TBLACStages WHERE TBLACStages.ACUnitID = @pACUnitID

OPEN @ACUnitCursor

FETCH NEXT FROM @ACUnitCursor INTO @ACStageID

WHILE @@FETCH_STATUS = 0 
BEGIN

INSERT INTO TBLACStages ([ACUnitID] ,[col1] ,[col2] ,[...] ,[coln]) SELECT @NewACUnitID ,[col1] ,[col2] ,[...] ,[coln] FROM TBLACStages WHERE TBLACStages.ACStageID = @ACStageID

SELECT @NewACStageID = SCOPE_IDENTITY()

INSERT INTO TBLACUpgrade ([ACStageID] ,[col1] ,[col2] ,[...] ,[coln]) SELECT @NewACStageID ,[col1] ,[col2] ,[...] ,[coln] FROM TBLACUpgrade WHERE TBLACUpgrade.[ACStageID] = @ACStageID

FETCH NEXT FROM @ACUnitCursor INTO @ACStageID 
END

CLOSE @ACUnitCursor DEALLOCATE @ACUnitCursor

END

GO

4 回复 | 直到 14 年前

Quassnoi 14 年前

CREATE TABLE t_parent (id INT NOT NULL PRIMARY KEY IDENTITY, value VARCHAR(100))
CREATE TABLE t_child (id INT NOT NULL PRIMARY KEY IDENTITY, parent INT NOT NULL, value VARCHAR(100))
CREATE TABLE t_grandchild (id INT NOT NULL PRIMARY KEY IDENTITY, child INT NOT NULL, value VARCHAR(100))

INSERT
INTO    t_parent (value)
VALUES  ('Parent 1')

INSERT
INTO    t_parent (value)
VALUES  ('Parent 2')

INSERT
INTO    t_child (parent, value)
VALUES  (1, 'Child 2')

INSERT
INTO    t_child (parent, value)
VALUES  (2, 'Child 2')

INSERT
INTO    t_grandchild (child, value)
VALUES  (1, 'Grandchild 1')

INSERT
INTO    t_grandchild (child, value)
VALUES  (1, 'Grandchild 2')

INSERT
INTO    t_grandchild (child, value)
VALUES  (2, 'Grandchild 3')

DECLARE @parent TABLE (oid INT, nid INT)
DECLARE @child TABLE (oid INT, nid INT)

MERGE
INTO    t_parent
USING   (
        SELECT  id, value
        FROM    t_parent
        ) p
ON      1 = 0
WHEN NOT MATCHED THEN
INSERT  (value)
VALUES  (value)
OUTPUT  p.id, INSERTED.id
INTO    @parent;
SELECT  *
FROM    @parent
MERGE
INTO    t_child
USING   (
        SELECT  c.id, p.nid, c.value
        FROM    @parent p
        JOIN    t_child c
        ON      c.parent = p.oid
        ) c
ON      1 = 0
WHEN NOT MATCHED THEN
INSERT  (parent, value)
VALUES  (nid, value)
OUTPUT  c.id, INSERTED.id
INTO    @child;
SELECT  *
FROM    @child;
INSERT
INTO    t_grandchild (child, value)
SELECT  c.nid, gc.value
FROM    @child c
JOIN    t_grandchild gc
ON      gc.child = c.oid
SELECT  *
FROM    t_grandchild

Matthew 14 年前

好的,这是 MERGE 我提出了一个基于Quassnoi的解决方案。我应该适当地工作,而不是 CURSOR

DECLARE @parent TABLE (oid BIGINT, nid BIGINT)
DECLARE @child TABLE (oid BIGINT, nid BIGINT)

MERGE
INTO    TBLACUnits T
USING   (SELECT [col1], [...], [coln] FROM TBLACUnits WHERE ID = @pID) S

ON      1 = 0
WHEN NOT MATCHED THEN
INSERT  ([ACUnitID]
   ,[col1]
   ,[...]
   ,[coln])
VALUES  (S.[ACUnitID]
   ,S.[col1]
   ,S.[...]
   ,S.[coln]])
OUTPUT  S.ACUnitID, INSERTED.ACUnitID
INTO    @parent;

MERGE
INTO    TBLACStages T
USING   (
  SELECT  tt.[nid] 
                       ,TBLACStages.[col1]
                       ,TBLACStages.[...]
                       ,TBLACStages.[coln]
  FROM TBLACStages
  JOIN @parent tt ON tt.oid = TBLACStages.ACUnitID
  ) S
ON      1 = 0
WHEN NOT MATCHED THEN
INSERT  ([ACUnitID]
   ,[col1]
   ,[...]
   ,[coln])
VALUES  ([nid]
   ,[col1]
   ,[...]
   ,[coln])
OUTPUT  S.[ACStageID], INSERTED.[ACStageID]
INTO    @child;

INSERT INTO TBLACUpgrade 
([ACStageID]
   ,[col1]
   ,[...]
   ,[coln])
SELECT  c.[nid]
   ,TBLACUpgrade.[col1]
   ,TBLACUpgrade.[...]
   ,TBLACUpgrade.[coln]
FROM    @child c
JOIN    TBLACUpgrade
 ON      TBLACUpgrade.ACStageID  = c.oid

Josh Crozier HBP 9 年前

我看到这篇文章时,我几乎被它的复杂性吓得喘不过气来,但它看起来确实不错。当我需要克隆或复制包含子表或子表的表时,我只需向表中添加一个名为 PreCloneControl

Declare @OldControl int = 123456

Declare @TT1 Table
(
TT1Control [int] IDENTITY(1,1) NOT NULL,
SomeData nvarchar(20)
)

insert into @TT1
(
SomeData
)
Select SomeDate from LiveTable where LTControl = @OldControl


Declare @NewControl int = SCOPE_IDENTITY()


Declare @TempTT2 Table
(
TT2Control int IDENTITY(1,1) NOT NULL,
TT2TT1FKControl int,
TT2ChildData nvarchar(20),
TT2ModUser nvarchar(100)
)

insert into @TempTT2
(
TT2TT1FKControl,TT2ChildData,TT2ModUser
)
Select @NewControl, TT2ChildData, Cast(TT2Control as nvarchar(100))
From TT2 where TT2TT1FKControl = @OldControl

Select * from @TempTT2

Declare @TT3 Table
(
TT3Control int IDENTITY(1,1) NOT NULL,
TT3TT2FKControl int,
TT3GrandChildData nvarchar(50),
TT3OldTT2Control int
)

Insert Into @TT3
(
TT3TT2FKControl,TT3GrandChildData,TT3OldTT2Control
)
Select t.TT2Control, BookItemItemNumber,TT2.TT2Control
From TT2 inner join GrandChildTable on TT2Control = GCTFKControl
       ,@TempTT2 as t
Where
TT2TT1FKControl = @OldControl
and  t.TT2ModUser = Cast(TT2Control as nvarchar(100))

Select * From @TT3

Update @TempTT2 set TT2ModUser = 'UserName' Where TT2TT1FKControl = @NewControl

Select * from @TempTT2

Luka Milani 14 年前

要提高SP的速度,可以添加另一条语句 FOR READ ONLY

    ...

SET @ACUnitCursor = CURSOR LOCAL FAST_FORWARD FOR 

SELECT ACStageID FROM TBLACStages WHERE TBLACStages.ACUnitID = @pACUnitID

FOR READ ONLY  -- add this to increase the speed

OPEN @ACUnitCursor

FETCH NEXT FROM @ACUnitCursor INTO @ACStageID

...