SQL - 更新，插入或替代触发器？

Question

如果更新或插入值到我的表中的字段之一，我想检查该值不包含一些字符。如果是这样，不要插入任何东西。 我这样做“而不是”触发器，但它只适用于插入的行，而不适用于更新的行。我做错了什么？我为这项任务选择了正确的触发器吗？

ALTER TRIGGER trg_MakeSureOfCleanDescription 
ON [dbo].[Car] 
instead OF INSERT 
AS 
    BEGIN 
     DECLARE @CharPosition_Inserted INT; 

     SET @CharPosition_Inserted = 0; 

     DECLARE @CharPosition_Updated INT; 

     SET @CharPosition_Updated = 0; 

     SELECT @CharPosition_Inserted = CHARINDEX('<', inserted.Description) 
     FROM inserted 

     --select @CharPosition_Updated = CHARINDEX('<', inserted.Description) from 
     IF(@CharPosition_Inserted = 0/*and @CharPosition_Updated = 0*/)--only if the description is html free, insert it. Otherwise don't insert nothing. 
     BEGIN 
      PRINT 'no html. inserting.' 

      INSERT INTO Car 
         ([Year], 
         [Make], 
         [Model], 
         [Price], 
         [ExtColor], 
         [IntColor], 
         [Body], 
         [Engine], 
         [Transmission], 
         [Miles], 
         [VIN], 
         [Description], 
         [MainImage], 
         [VideoFile], 
         [StockNumber], 
         [Sold]) 
      SELECT [Year], 
        [Make], 
        [Model], 
        [Price], 
        [ExtColor], 
        [IntColor], 
        [Body], 
        [Engine], 
        [Transmission], 
        [Miles], 
        [VIN], 
        [Description], 
        [MainImage], 
        [VideoFile], 
        [StockNumber], 
        [Sold] 
      FROM inserted 
     END 
    END 

谢谢。我的代码：

Answer 1

您只是检查插入操作。更新处理完全不同，必须在单独的触发器中处理。由于Insert和Before触发器之间存在触发器，所以在Update和Delete触发器之前和之后都有。在你的情况下，你需要为更新场景创建另一个触发器。

https://technet.microsoft.com/en-us/library/ms188601%28v=sql.105%29.aspx