Sql 如何解决;自引用表与外键约束“冲突”;
我正在创建一个简单的表,其中包含自动生成的Sql 如何解决;自引用表与外键约束“冲突”;,sql,sql-server,sql-server-2008,Sql,Sql Server,Sql Server 2008,我正在创建一个简单的表,其中包含自动生成的员工id,前缀如下 sale_900000,sale_900001,sale_900002,sale_900003 它是一个自引用表 在表中插入数据时,会出现如下错误: *Msg 547,16级,状态0,程序tr_生成emp_id,第42行 INSERT语句与外键相同表约束“Registration\u Registration”冲突。冲突发生在数据库“test”、表“dbo.Registration”、列“empid”中* 对于自动员工id,我在表
员工id
,前缀如下
sale_900000,sale_900001,sale_900002,sale_900003
它是一个自引用表
在表中插入数据时,会出现如下错误:
*Msg 547,16级,状态0,程序tr_生成emp_id,第42行INSERT语句与外键相同表约束“Registration\u Registration”冲突。冲突发生在数据库“test”、表“dbo.Registration”、列“empid”中* 对于自动员工id,我在表上使用
而不是insert
触发器
这是我的桌子
CREATE TABLE [dbo].[Registration](
[empid] [varchar](40) NOT NULL,
[id] [int] IDENTITY(900000,1) NOT NULL,
[First_Name] [varchar](40) NULL,
[Last_Name] [varchar](40) NULL,
[Address] [varchar](40) NULL,
[E_Mail] [varchar](40) NULL,
[Country] [varchar](40) NULL,
[Mobile_No] [varchar](40) NULL,
[Designation] [varchar](40) NULL,
[managerID] [varchar](40) NULL,
CONSTRAINT [PK_Registration] PRIMARY KEY CLUSTERED
(
[empid] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
ALTER TABLE [dbo].[Registration] WITH CHECK ADD CONSTRAINT [Registration_Registration] FOREIGN KEY([managerID])
REFERENCES [dbo].[Registration] ([empid])
这是我的扳机
ALTER TRIGGER [dbo].[tr_generate_emp_id] ON [dbo].[Registration]
INSTEAD OF INSERT
AS
BEGIN
DECLARE @id INT
DECLARE @id1 INT
DECLARE @id_s VARCHAR(50)
DECLARE @empid VARCHAR(50)
DECLARE @First_Name VARCHAR(50)
DECLARE @Last_Name VARCHAR(50)
DECLARE @Address VARCHAR(50)
DECLARE @E_Mail VARCHAR(50)
DECLARE @Country VARCHAR(50)
DECLARE @Mobile_No VARCHAR(50)
DECLARE @Designation VARCHAR(50)
DECLARE @managerID VARCHAR(50)
SELECT @id = Id
FROM dbo.Registration
IF @id IS NULL
SET @id = 899999
SET @id1 = @id + 1
SELECt @First_Name = First_Name ,
@Last_Name = Last_Name ,
@Address = Address ,
@E_Mail = E_Mail ,
@Country = Country ,
@Mobile_No = Mobile_No ,
@Designation = Designation ,
@managerID = managerID
FROM INSERTED
SET @id_s = CONVERT(VARCHAR(50), @id1)
SET @empid = 'Sale_' + @id_s
INSERT INTO dbo.Registration
( empid ,
First_Name ,
Last_Name ,
Address ,
E_Mail ,
Country ,
Mobile_No ,
Designation ,
managerID
)
VALUES ( @empid , -- empid - varchar(40)
@First_Name , -- First_Name - varchar(40)
@Last_Name , -- Last_Name - varchar(40)
@Address , -- Address - varchar(40)
@E_Mail , -- E_Mail - varchar(40)
@Country, -- Country - varchar(40)
@Mobile_No , -- Mobile_No - varchar(40)
@Designation , -- Designation - varchar(40)
@managerID -- managerID - varchar(40)
)
END
我正在插入
INSERT INTO dbo.Registration
( empid ,
First_Name ,
Last_Name ,
Address ,
E_Mail ,
Country ,
Mobile_No ,
Designation ,
managerID
)
VALUES ( '' , -- empid - varchar(40)
'admin' , -- First_Name - varchar(40)
'jon' , -- Last_Name - varchar(40)
's-24' , -- Address - varchar(40)
'abc@gmail.com' , -- E_Mail - varchar(40)
'india' , -- Country - varchar(40)
'098735322211' , -- Mobile_No - varchar(40)
'manager' , -- Designation - varchar(40)
'' -- managerID - varchar(40)
)
和错误
Msg 547, Level 16, State 0, Procedure tr_generate_emp_id, Line 42
The INSERT statement conflicted with the FOREIGN KEY SAME TABLE constraint "Registration_Registration". The conflict occurred in database "test", table "dbo.Registration", column 'empid'.
The statement has been terminated.
主要的问题是你首先要做的就是这样。我刚看完你的扳机。刚刚将empid更改为计算字段
CREATE TABLE [dbo].[Registration](
[empid] AS ('Sale_' + Convert(Varchar(50),id)) PERSISTED,
[id] [int] IDENTITY(900000,1) NOT NULL,
[First_Name] [varchar](40) NULL,
[Last_Name] [varchar](40) NULL,
[Address] [varchar](40) NULL,
[E_Mail] [varchar](40) NULL,
[Country] [varchar](40) NULL,
[Mobile_No] [varchar](40) NULL,
[Designation] [varchar](40) NULL,
[managerID] [varchar](40) NULL,
CONSTRAINT [PK_Registration] PRIMARY KEY CLUSTERED
(
[empid] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
在你的扳机里我想这条线
SELECT @id = Id
是用来阅读的
SELECT @id = MAX(Id)
我很惊讶你没有因此收到PK违规错误。FK冲突错误只能是由于尝试插入与empid值不匹配的MangerId值(从代码中我可以看到)。因此,请检查您提供的managerId值
我重新设置了触发器,但我认为@Love2Learn可能有更好的解决方案
ALTER TRIGGER [dbo].[tr_generate_emp_id] ON [dbo].[Registration]
INSTEAD OF INSERT
AS
BEGIN
DECLARE @id INT
-- Get the last id used.
SELECT @id = MAX(Id)
FROM dbo.Registration
IF @id IS NULL
SET @id = 899999
WITH MyInserted AS (SELECT
ROW_NUMBER() OVER(ORDER BY E_Mail) AS rownum-- Email is just a random order by here. Could be anything you want.
,*
FROM inserted)
INSERT INTO dbo.Registration
( empid ,
First_Name ,
Last_Name ,
Address ,
E_Mail ,
Country ,
Mobile_No ,
Designation ,
managerID
)
SELECT -- add the last id used with the rownum (ranges from 1 to num of rows)
'Sale_'+CONVERT(VARCHAR(50), @id+rownum) -- empid - varchar(40)
First_Name, -- First_Name - varchar(40)
Last_Name, -- Last_Name - varchar(40)
Address, -- Address - varchar(40)
E_Mail, -- E_Mail - varchar(40)
Country, -- Country - varchar(40)
Mobile_No, -- Mobile_No - varchar(40)
Designation, -- Designation - varchar(40)
ManagerID -- managerID - varchar(40)
FROM MyInserted
END
您的第一个问题是…触发器是基于集合的,而不是基于行的。我相信问题在于你创造了一个永无止境的触发器。您尝试插入到触发触发器的表中,该触发器表示,而不是插入到表中做一些工作,然后插入到表中,但我相信插入将再次触发触发器,从而重新启动流程,并导致无休止的循环。在插入记录后,我会根据一些逻辑对插入的记录进行更新。第二个问题是。。。您
在触发器中选择@id
,可能会返回任何现有行。无法保证此逻辑将为您提供一个未使用的@id值。改为使用MAX()
,或者更好地使用after触发器中现有的IDENTITY
列。这样可以查看整个问题@Love2Learn的答案要好得多,anway触发器通常是要避免的,如下所述: