SQL触发器仅在删除期间返回一条记录

Question

下面是我为SQL数据库中的表创建的触发器（我们正在运行SQL Server 2008）。我们将要进行更新，插入和删除，因此我们创建了这个触发器和一个“存储”表（TransactionLog）来捕获所有的活动。到目前为止，这个触发器对插入和更新非常有用。所有记录都以“所有适当的值”存储在“存储”表中。

但是，当我们尝试删除超过一条记录时，会出现问题。此触发器捕获并发送到“存储”表的唯一记录是删除的最后一条记录。所有其他人都迷路了。

CREATE TRIGGER [dbo].[trg_Agent_ALL] 
ON [dbo].[Agent] 

FOR INSERT, UPDATE, DELETE 
AS 
BEGIN 

--TransactionLog variables 
DECLARE @tableName char(25) = 'Agent' 
DECLARE @transDate datetime 
DECLARE @lastChangeOperator char(6) 
DECLARE @tableString char(255) 
DECLARE @action char(1) = 'I' 
DECLARE @userId char(25) 

--Trigger table variables 
DECLARE @sNumber char(10) 
DECLARE @controlId char(3) 
DECLARE @entityType char(1) 
DECLARE @firstName nvarchar(50) 
DECLARE @lastName nvarchar(50) 
DECLARE @suffix nvarchar(10) 
DECLARE @corpName nvarchar(100) 


IF EXISTS (SELECT * FROM deleted) 
    BEGIN 
     SET @action = 
      CASE  
       WHEN EXISTS (SELECT * FROM inserted) THEN 'U' 
       ELSE 'D' 
      END 
    END 

IF @action = 'D' 
    BEGIN 
     SELECT @sNumber = sNumber, @lastChangeOperator = LastChangeOperator, @transDate = LastChangeDate, @entityType = EntityType, 
     @firstName = FirstName, @lastName = LastName, @suffix = NameSuffix, @corpName = CorporateName, @controlId = ControlId 
     FROM deleted 

     IF @firstName IS NULL SET @firstName = 'NULL' 
     IF @lastName IS NULL SET @lastName = 'NULL' 
     IF @suffix IS NULL SET @suffix = 'NULL' 
     IF @corpName IS NULL SET @corpName = 'NULL' 
     IF @controlId IS NULL SET @controlId = 'NULL' 

     SET @tableString = 'sNum:' + @sNumber + ' ' + 'EntType:' + @entityType + ' ' + 'Fname:' + @firstName + ' ' + 'Lname:' + @lastname + ' ' + 'suf:' + @suffix + 
      ' ' + 'crpName:' + @corpName + ' ' + 'crlId:' + @controlId 
    END 
ELSE 
    BEGIN 
     SELECT @sNumber = SymetraNumber, @lastChangeOperator = LastChangeOperator, @transDate = LastChangeDate, @entityType = EntityType, 
     @firstName = FirstName, @lastName = LastName, @suffix = NameSuffix, @corpName = CorporateName, @controlId = ControlId 
     FROM inserted 

     IF @firstName IS NULL SET @firstName = 'NULL' 
     IF @lastName IS NULL SET @lastName = 'NULL' 
     IF @suffix IS NULL SET @suffix = 'NULL' 
     IF @corpName IS NULL SET @corpName = 'NULL' 
     IF @controlId IS NULL SET @controlId = 'NULL' 

     SET @tableString = 'sNum:' + @sNumber + ' ' + 'EntType:' + @entityType + ' ' + 'Fname:' + @firstName + ' ' + 'Lname:' + @lastname + ' ' + 'suf:' + @suffix + 
      ' ' + 'crpName:' + @corpName + 'crlId:' + @controlId 
    END 

INSERT INTO TransactionLog (TransactionDate, Operator, TableName, Action, TableString, UserId) 
VALUES (@transDate, 'Op', @tableName, @action, @tableString, @lastChangeOperator) 

END 

根据以下评论，我已经更改了删除部分中的SQL代码。硬编码值似乎正在工作，但我把它们放在那里只是为了显示这些值的主要原因是我需要这些特定列的值。我在上面的代码中使用这些值设置了变量（请参阅DECLARE语句）。但是，这给我以下错误信息：

Conversion failed when converting the varchar value 'P' to data type int. 

此错误来自内部SELECT语句中的EntityType属性。令我困惑的是，此列的数据类型设置为char（1），而TableString列（连接值的目的地）的数据类型为nvarchar（255）。不知道这里的“INT”是哪里来的？

IF @action = 'D' 
    BEGIN 
     INSERT INTO TransactionLog (TransactionDate, Operator, TableName, Action, TableString, UserId) 
     SELECT LastChangeDate, 'Op', 'Agent', 'D', 
     (SELECT CAST(CAST(sNumber as nvarchar) + ' ' + EntityType + ' ' + ISNULL(FirstName, ' ') + ' ' + ISNULL(LastName, ' ') + ' ' + ISNULL(NameSuffix, ' ') + ' ' + 
       ISNULL(CorporateName, ' ') + ' ' + ISNULL(CAST(ControlId as nvarchar), ' ') AS nvarchar) as TableString 
     FROM deleted), LastChangeOperator 
     FROM deleted 
    END 
ELSE 

编辑

通过铸造sNumber和控件ID字段为nvarchar我能搬过去我以前的错误消息。现在，但是我收到一个不同的错误信息贴在下面：

Subquery returned more than 1 value. This is not permitted when the subquery follows =, !=, <, <= , >, >= or when the subquery is used as an expression. 

最后编辑

改变子查询，像这样让我多删除的记录返回到审计表，因为我是唯一一个请求记录一次。

IF @action = 'D' 
    BEGIN 
     INSERT INTO TransactionLog (TransactionDate, Operator, TableName, Action, TableString, UserId) 
      SELECT LastChangeDate, 'Op', 'Agent', 'D', 
      CAST('SymNum:' + CAST(SymetraNumber as nvarchar(30)) + ' entType:' + EntityType + ' Fname:' + ISNULL(FirstName, 'NULL') + ' Lname:' + ISNULL(LastName, 'NULL') + 
      ' suff:' + ISNULL(NameSuffix, 'NULL') + ' corpName:' + ISNULL(CorporateName, 'NULL') + ' ctrlId:' + ISNULL(CAST(ControlId as nvarchar(30)), 'NULL') AS nvarchar(30)) as TableString 
      , LastChangeOperator 
     FROM deleted 
    END 
ELSE 

Answer 1

这select @sNumber = sNumber, ..语法将覆盖变量一次的每一行，所以你最终只与最后一排的价值观。

然后你也做一个insert into ... values (...)，它只能插入一行。

你应该尝试重写它的形式：

insert into TransactionLog (...) 
select sNumber, ... from deleted 

可以使用ISNULL(lastname, 'NULL')，而不是你的if语句。