SqlServer触发器判断对表操作类型（增、删、改）并将修改后的数据映射到新表

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触发器要实现的功能：

（1）获取对表Table1数据操作操作类型（insert、delete或update）。

（2）将表修改后的数据保存到表Table2（该表结构与Table1表结构类似）。

例如：

1>向表Table1添加数据1，表保存后，将数据1添加到表Table2，并将操作类型：insert，保存到表Table2的ChangeType列。

2>修改表Table1，将数据1改成数据2，表保存后，将数据2添加到表Table2，并将操作类型：update，保存到表Table2的ChangeType列。

3>删除表Table1数据1，表保存后，将数据2添加到表Table2，并将操作类型：delete，保存到表Table2的ChangeType列。

表结构：

（1）表Table1

 CREATE TABLE Table1(
     [ID] [BIGINT] IDENTITY(1,1) NOT NULL,
     [Name] [NVARCHAR](20) NULL,
     [Sex] [NVARCHAR](2) NULL,
     [Address] [NVARCHAR](50) NULL,
     [Age] [INT] NULL,
     [Birthday] [DATE] NULL
 ) ON [PRIMARY]

（2）表Table2

 CREATE TABLE Table2(
      [ID] [BIGINT] IDENTITY(1,1) NOT NULL,
      [Name] [NVARCHAR](20) NULL,
      [Sex] [NVARCHAR](2) NULL,
      [Address] [NVARCHAR](50) NULL,
      [Age] [INT] NULL,
      [Birthday] [DATE] NULL，
      [ChangeType] [NVARCHAR](50) NOT NULL
  ) ON [PRIMARY]

触发器Tri_Table1

 CREATE  TRIGGER [Tri_Table1] ON [Table1]
     --After触发器，对表进行insert、delete、update后触发
     AFTER INSERT, DELETE, UPDATE
 AS
     BEGIN
         BEGIN TRY
             BEGIN TRAN;
             DECLARE @maxID NVARCHAR(50) ,
                 @inserted INT ,
                 @deleted INT ,
                 @ChangeType NVARCHAR(20);
             SELECT  @inserted = COUNT(1)
             FROM    Inserted;
             SELECT  @deleted = COUNT(1)
             FROM    Deleted;
             --判断对表Table1的操作类型
             IF @inserted > 0
                 AND @deleted = 0
                 BEGIN
                     SET @ChangeType = 'INSERT';
                 END;
             ELSE
                 IF @inserted > 0
                     AND @deleted > 0
                     BEGIN
                         SET @ChangeType = 'UPDATE';
                     END;
                 ELSE
                     IF @inserted = 0
                         AND @deleted > 0
                         BEGIN
                             SET @ChangeType = 'DELETE';
                         END;
             IF @ChangeType = 'DELETE'
                 BEGIN
                     SELECT  @maxID = Id
                     FROM    Deleted;
                     --如果对Table1同一条数据，进行多次操作，则Table2只保存最新数据
                     IF EXISTS ( SELECT  COUNT(1)
                                 FROM    Table2
                                 WHERE   Id = @maxID )
                         BEGIN
                             DELETE  FROM Table2
                             WHERE   Id = @maxID;
                         END;
                     INSERT  INTO Table2
                             (
                             )
                             SELECT  ID,
                                     Name,
                                     Sex,
                                     Address,
                                     Age,
                                     Birthday,
                                     @ChangeType AS ChangeType
                             FROM    Deleted;
                 END;
              ELSE
                 BEGIN
                     SELECT  @maxID = Id
                     FROM    Inserted;
                     IF EXISTS ( SELECT  COUNT(1)
                                 FROM    Table2
                                 WHERE   Id = @maxID )
                         BEGIN
                             DELETE  FROM Table2
                             WHERE   Id = @maxID;
                         END;
                     INSERT  INTO Table2
                             (
                                 ID,
                                 Name,
                                 Sex,
                                 Address,
                                 Age,
                                 Birthday,
                                 ChangeType
                             )
                             SELECT  ID,
                                     Name,
                                     Sex,
                                     Address,
                                     Age,
                                     Birthday,
                                     @ChangeType AS ChangeType
                             FROM    Inserted
                 END;
             COMMIT TRAN;
         END TRY
         BEGIN CATCH
             IF XACT_STATE() = -1
                 ROLLBACK TRAN;
         END CATCH;
     END;