T-SQL插入触发器在多个表上插入,更新if条件

Question

我有一些问题试图解决SQL触发器自动设置用户被阻止并创建包含另一个表中的日期的块记录,如果他们的截止日期等于设置日期.

问题是当插入触发器触发时,执行print语句并发生插入,但是插入到表中却没有,或者更新语句？有谁能解释为什么？

注意:insert和Update语句在自己执行时都可以.

账户表

CREATE TABLE [dbo].[Account](
[AccountNo] [int] IDENTITY(1,1) NOT NULL,
[CustomerNo] [int] NOT NULL,
[PaymentNo] [int] NULL,
[CreditNo] [int] NULL,
[BlockID] [dbo].[number] NULL,
[Balence] [dbo].[currency] NOT NULL,
[AmountDue] [dbo].[currency] NOT NULL,
[DueDate] [dbo].[dates] NULL,
[AutherisedBy] [nvarchar](50) NOT NULL,
[DateCreated] [date] NOT NULL,

BLOCKEDUSER TABLE

CREATE TABLE [dbo].[BlockedUsers](
[BlockID] [int] IDENTITY(1,1) NOT NULL,
[DateEnforced] [dbo].[dates] NOT NULL,
[Blocked] [dbo].[switch] NOT NULL,

触发

ALTER TRIGGER [dbo].[Add_Blocked_User]
ON [dbo].[Account]
FOR INSERT
AS  
BEGIN
SET NOCOUNT ON;

Declare @ID int
Select @ID = [AccountNo] from inserted  
If(Select [DueDate] from inserted) = '2011-01-01'

INSERT INTO dbo.BlockedUsers(DateEnforced,Blocked)
VALUES (GETDATE(),1)
PRINT 'New Block Date Added'

UPDATE Account 
Set BlockID = IDENT_CURRENT('BlockID')
where @ID = @ID
PRINT 'Account Blocked'

END

GO

完全工作示例:使用下面的帮助完成.

ALTER TRIGGER [dbo].[Add_Blocked_User]
ON [dbo].[Account]
AFTER INSERT
AS 
BEGIN

SET NOCOUNT ON;

Declare @ID int
Select @ID = [AccountNo] from inserted  
 If(Select [DueDate] from inserted)Not Between (select CONVERT(date, getdate() - 30)) And (select CONVERT(date, getdate()))
Begin
    INSERT INTO dbo.BlockedUsers(DateEnforced,Blocked)
    VALUES (GETDATE(),1)
    PRINT 'New Block Date Added'

    UPDATE Account 
    Set BlockID = (Select Max(BlockID) From BlockedUsers)
    where [AccountNo] = (Select [AccountNo] from inserted)  
    PRINT 'Account Blocked'
 End

 END

GO

Answer 1

将IF在Transact-SQL语句要求的条件后一条语句:

IF condition
  statement;

如果要在同一分支中执行多个语句,则必须将它们括在BEGIN/ END"括号"中:

IF condition
BEGIN
  statement;
  statement;
  ...
END;

在触发器中,仅根据(Select [DueDate] from inserted) = '2011-01-01'条件的结果执行INSERT语句.对于PRINT和UPDATE,它们无条件地执行,即在每次插入之后执行Account.所以,你可能需要添加BEGIN和END周围的INSERT,UPDATE和两个打印:

...
If(Select [DueDate] from inserted) = '2011-01-01'
BEGIN
INSERT INTO dbo.BlockedUsers(DateEnforced,Blocked)
VALUES (GETDATE(),1);
PRINT 'New Block Date Added';

UPDATE Account 
Set BlockID = IDENT_CURRENT('BlockID')
where @ID = @ID;
PRINT 'Account Blocked';
END;
...