更新触发器如何删除旧记录

Question

我在表A上创建了插入触发器，在表A中插入记录时，只要在表A上发生插入操作就行了。这很好，但是如果我在表A上使用更新触发器，它会在表中插入更新记录B，但不会删除表B中的旧记录。如何获得期望的结果？

ALTER TRIGGER trigger1 on tableA 
FOR UPDATE 

AS 
BEGIN 

IF NOT EXISTS (SELECT C.column1 FROM tableB C INNER JOIN INSERTED I ON C.column1 = I.column1 WHERE C.column1 = I.column1 AND C.column2 = I.column2) 
INSERT INTO tableB (column1 , column2) 
    SELECT column1 , column2 
    FROM INSERTED I 
    WHERE RecordTypeId IS NOT NULL 
    GROUP BY column1 , column2 
    ORDER BY column1 , column2 

END 

Answer 1

请检查下面的SQL Server Update trigger其使用内部删除表

create TRIGGER trigger1 on tableA 
FOR UPDATE 

AS 
BEGIN 

DELETE tableB 
FROM tableB b 
INNER JOIN deleted d 
    on b.column1 = d.column1 
    and b.column2 = d.column2 


INSERT INTO tableB (column1 , column2) 
    SELECT column1 , column2 
    FROM INSERTED 

使用生产之前请测试从目标表中删除。