SQL Server “复制”表结构，创建_Log表及触发器

实例效果：

实现表数据的增修删时，记录日志。

1.“复制”现有表，

创建相应的_Log表；

（注意点：

通过select union all 的方式，避免了IDENTITY 的“复制”，
即如果原表有 PK 如 ID Identity，_Log表 仅“复制”ID int，“不复制” Identity属性，
以便 Insert Update Delete时，可以Insert到Log表。）

2.对现有表，创建Insert，Update,Delete的触发器，

并将相应数据 记录到对应的_Log表

相应代码如下：

BEGIN TRAN
BEGIN TRY  

--定义TAB_CURSOR
DECLARE TAB_CURSOR CURSOR read_only
FOR
   SELECT name FROM SysObjects Where XType='U'
  -- AND name = N'T01ConstItem'
  and [name] <> N'dtproperties'
   ORDER BY Name;

--打开
OPEN TAB_CURSOR

DECLARE @P_TabName NVARCHAR(200);
DECLARE @P_TabName_Log NVARCHAR(200);
DECLARE @P_Create_Log_Tab NVARCHAR(4000);
DECLARE @P_Create_Trig_I NVARCHAR(4000);
DECLARE @P_Create_Trig_U NVARCHAR(4000);
DECLARE @P_Create_Trig_D NVARCHAR(4000);

FETCH NEXT FROM TAB_CURSOR
           INTO @P_TabName
--循环
WHILE (@@FETCH_STATUS <> -1)
BEGIN
   IF (@@FETCH_STATUS <> -2)
    BEGIN
    SET @P_TabName_Log = CONCAT(@P_TabName,N'_Log');

    SET @P_Create_Log_Tab = N' SELECT * ';
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,N' ,N''I '' AS Action');
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,N' ,Getdate() AS ActionDate ');
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,N' INTO ');
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,@P_TabName_Log );
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,N' FROM  ' );
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,@P_TabName);
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,N' UNION ALL ');
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,N' SELECT TOP (1) * ');
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,N' ,N''I '' AS Action');
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,N' ,Getdate() AS ActionDate ');
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,N' FROM  ' );
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab,@P_TabName);
    SET @P_Create_Log_Tab = CONCAT(@P_Create_Log_Tab, N' WHERE 1=0 ; ');

    EXEC( @P_Create_Log_Tab);

    --SET @P_Create_Log_Tab = CONCAT(N' SET IDENTITY_INSERT ',@P_TabName_Log ,' ON ');
    --EXEC( @P_Create_Log_Tab);

    SET @P_Create_Trig_I = N' create trigger ';
    SET @P_Create_Trig_I = CONCAT(@P_Create_Trig_I,N' trig_',@P_TabName,N'_I ');
    SET @P_Create_Trig_I = CONCAT(@P_Create_Trig_I,N' on ',@P_TabName,N' after INSERT as ');
    SET @P_Create_Trig_I = CONCAT(@P_Create_Trig_I, N' begin ');
    SET @P_Create_Trig_I = CONCAT(@P_Create_Trig_I, N'insert into ',@P_TabName_Log );
    SET @P_Create_Trig_I = CONCAT(@P_Create_Trig_I,N' select * , N''I'',Getdate() from Inserted ; ' );
    SET @P_Create_Trig_I = CONCAT(@P_Create_Trig_I, N'end ');

    --select @P_Create_Trig_I;

    EXEC( @P_Create_Trig_I);

    SET @P_Create_Trig_U = N' create trigger ';
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U,N' trig_',@P_TabName,N'_U ');
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U,N' on ',@P_TabName,N' after UPDATE as ');
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U, N' begin ');
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U, N'insert into ',@P_TabName_Log );
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U,N' select * , N''UD'',Getdate() from Deleted ; ' );
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U, N'insert into ',@P_TabName_Log );
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U,N' select * , N''UI'',Getdate() from Inserted ; ' );
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U, N'end ');
    EXEC( @P_Create_Trig_U);

    SET @P_Create_Trig_U = N' create trigger ';
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U,N' trig_',@P_TabName,N'_D ');
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U,N' on ',@P_TabName,N' after DELETE as ');
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U, N' begin ');
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U, N'insert into ',@P_TabName_Log );
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U,N' select * , N''D'',Getdate() from Deleted ; ' );
    SET @P_Create_Trig_U = CONCAT(@P_Create_Trig_U, N'end ');
    EXEC( @P_Create_Trig_U);

    END
   FETCH NEXT FROM TAB_CURSOR INTO @P_TabName
END

--关闭
CLOSE TAB_CURSOR
--释放
DEALLOCATE TAB_CURSOR

COMMIT TRAN;  

END TRY
BEGIN CATCH
    SELECT ERROR_MESSAGE() AS ErrorMessage
    ,ERROR_SEVERITY() AS ErrorSeverity
    ,ERROR_STATE() AS ErrorState
    ROLLBACK TRAN;
END CATCH