插入具有唯一 ID 的记录时无法在触发器上执行多行插入

Question

这是我的触发器：

ALTER TRIGGER DONORINFO_INSERT 
ON [dbo].[DONORINFO] INSTEAD OF INSERT
AS
    DECLARE @sequence AS VARCHAR(50) = '' 
    DECLARE @tranLen VARCHAR(10)

    SET @sequence = (SELECT TOP 1 SUBSTRING([DONORID], 3, 8) 
                     FROM [dbo].[DONORINFO] 
                     ORDER BY [DONORID] DESC)

    IF (@sequence IS NULL OR @sequence = '')
    BEGIN           
        SELECT @sequence = REPLICATE('0', 7 ) + '1'                  
    END
    ELSE            
    BEGIN           
        SELECT @tranLen = LEN(@sequence)
        SELECT @sequence = @sequence + 1    
        SELECT @tranLen = ABS(@tranLen - LEN(CAST(@sequence AS INT)))
        SELECT @sequence =   REPLICATE('0', @tranLen) + @sequence
    END     

    DECLARE @DONORID AS [nvarchar](50) = 'DN' + CONVERT(VARCHAR, @sequence) 

    INSERT INTO [dbo].[DONORINFO] ([DONORID], [DONORNAME])
        SELECT @DONORID, inserted.DONORNAME
        FROM inserted

在脚本的第一行，我正在阅读 DONORINFO table，我在其中检查了唯一 ID 是否存在。之后，我将把记录插入到那个 table 中。我第一次测试时，insert into select 脚本有效，但第二次时，它失败并发送并违反了主键错误。

但是如果我逐行测试插入，它会起作用。

这是行之有效的逐行插入脚本。

INSERT INTO [dbo].[DONORINFO] ([DONORID], [DONORNAME])
VALUES ('DN00000001', 'test')

如果我运行它两次，记录将是这样的：

DONORID     DONORNAME   
---------------------
DN00000001  test    
DN00000002  test

这是对 select 脚本的插入，但不起作用：

INSERT INTO [dbo].[DONORINFO] ([DONORID], [DONORNAME])
    SELECT
        '',
        [NameOfDonor] 
    FROM 
        [dbo].[_TEMPENDOWMENTFUND] AS ENDF
    WHERE 
        [ENDF].[NameOfDonor] NOT IN (SELECT [DONORNAME] 
                                     FROM [dbo].[DONORINFO])

_TEMPDOWMENTFUND 是我创建的 table，它将存储从 Excel 工作表迁移的数据，触发器的目的是生成一个唯一的 DONORID 对于 DONORINFO table 上插入的每条记录。

现在我的问题是，我想执行 insert into select 语句，这是一个多行插入，但我很难弄清楚我创建的触发器出了什么问题.

如有任何帮助，我们将不胜感激。谢谢。

Answer 1

将@sequence完全int（可能重命名为last_id），在最后添加字符。

要对行进行编号，请使用 ROW_NUMBER() in final select from INSERTED:

INSERT INTO [dbo].[DONORINFO] ([DONORID], [DONORNAME])
SELECT
  'DN' + REPLICATE('0', ABS(@len_you_need - LEN(t.generated_id))) + CAST (t.generated_id as varchar(100)),
  t.DONORNAME
FROM
(
SELECT
  i.DONORNAME, 
  @sequence+ROW_NUMBER()OVER(ORDER BY i.DONORNAME) as generated_id
FROM inserted i
) t

@len_you_need - 是您需要的 DONORID 的长度。我猜这可能是一个8个字符的常量。在您的来源中，您在这里计算：

SELECT @tranLen = LEN(@sequence)

t.rn 是在上面给出的子查询中生成的 "sequence" 值，它有 t 别名。为清楚起见，将其重命名为 generated_id。

这个区块：

BEGIN           
     SELECT @tranLen = LEN(@sequence)
     SELECT @sequence = @sequence + 1   
     SELECT @tranLen = ABS(@tranLen - LEN(CAST(@sequence AS INT)))
     SELECT @sequence =   REPLICATE('0', @tranLen) + @sequence
END

不再需要了。

Answer 2

这是@ivan-starostin 帮我解答的完整解决方案。

ALTER TRIGGER DONORINFO_INSERT ON [dbo].[DONORINFO]
INSTEAD OF INSERT, UPDATE
AS
DECLARE @sequence AS VARCHAR(50) = '' 
DECLARE @tranLen VARCHAR(10)

SET @sequence = (SELECT TOP 1 SUBSTRING([DONORID], 3, 8) FROM [dbo].[DONORINFO] ORDER BY [DONORID] DESC)

IF (@sequence IS NULL OR @sequence = '')
BEGIN           
    SELECT @sequence = REPLICATE('0', 7 )
END
ELSE            
BEGIN           
     SELECT @tranLen = LEN(@sequence)
     SELECT @sequence = @sequence + 1   
     SELECT @tranLen = ABS(@tranLen - LEN(CAST(@sequence AS INT)))
     SELECT @sequence =   REPLICATE('0', @tranLen) + @sequence
END     


INSERT INTO [dbo].[DONORINFO] ([DONORID], [DONORNAME])
SELECT
  'DN' + REPLICATE('0', ABS(8 - LEN(t.generated_id))) + CAST (t.generated_id        as varchar(100)),
  t.DONORNAME
FROM
(
SELECT
  i.DONORNAME, 
  @sequence+ROW_NUMBER()OVER(ORDER BY i.DONORNAME) as generated_id
FROM inserted i
) t

所以如果我运行下面那两个不同 insert into select...

INSERT INTO [dbo].[DONORINFO] ([DONORNAME])
SELECT 
[NameOfDonor] 
FROM [dbo].[_TEMPENDOWMENTFUND] AS ENDF
WHERE [ENDF].[NameOfDonor] NOT IN (SELECT [DONORNAME] FROM [dbo].[DONORINFO])

INSERT INTO [dbo].[DONORINFO] ([DONORNAME])
SELECT 
[NameOfDonor] 
FROM [dbo].[_TEMPENDOWED] AS ENDF
WHERE [ENDF].[NameOfDonor] NOT IN (SELECT [DONORNAME] FROM [dbo].[DONORINFO])

donorid 迭代将与这两个不同的 table 来源类似（出于保密原因，我已经省略了捐赠者姓名）。

DONORID DONORNAME (from _TEMPENDOWMENTFUND)
------------------------
DN00000001  test
DN00000002  test
DN00000003  test
DN00000004  test
DN00000005  test
DN00000006  test
DN00000007  test

DONORID DONORNAME (from _TEMPENDOWED)
------------------------
DN00000007  test
DN00000008  test
DN00000009  test
DN00000010  test
DN00000011  test
DN00000012  test
DN00000013  test

插入具有唯一 ID 的记录时无法在触发器上执行多行插入

Cannot perform multi-row insert on trigger when inserting record with unique id

sql

sql-server

triggers

stored-procedures

uniqueidentifier