我已根据以下帖子的第一个答案提供的信息实施了审计跟踪框架:
SQL Server history table – populate through SP or Trigger?
最终,我实现的框架每个表使用三个触发器,根据表的更改插入审计信息.
我的插入和删除审计触发器非常简单.但是,更新触发器要复杂得多,因为触发器必须检查以确定每个列是否处于审计控制之下,然后根据“已插入”和“已删除”列中的列值是否相等来执行插入操作我不想写不必要的审计记录.最后,我想知道是否有办法编写一个存储过程,通过允许我动态执行下面的insert语句来减少触发器中的代码量.基本上,我设想触发器使用处于审计控制下的每个列名触发sproc,然后存储过程将使用列名来执行下面的代码片段.目前,我在审计控制下的每个列都有以下代码,遗憾的是这会产生大量冗余代码.
建议更改后修订触发器
CREATE TRIGGER [dbo].[Audit_Customers_Update] ON [dbo].[Customers] FOR UPDATE AS select FirstName,LastName into #deleted from deleted; declare /*const*/ @TABLE_NAME sysname = '[table name]'; declare f cursor local forward_only read_only for select c.name,quotename(c.name,'[') from sys.columns c inner join sys.types t on c.system_type_id = t.system_type_id where c.object_id = object_id(@TABLE_NAME) and c.is_computed = 0 and c.is_identity = 0 and t.name not in ('text','image','timestamp','xml') and (substring(COLUMNS_UPDATED(),((c.column_id - 1) / 8) + 1,1) & power(2,(c.column_id - 1) % 8)) > 0 ; declare @field_name sysname,@field_name_sanitised sysname; create table #results (row_id int not null,field_name sysname not null,oldval nvarchar(150) null,newval nvarchar(150) null); -- For each changed field,insert what exactly changed into #results open f; fetch next from f into @field_name,@field_name_sanitised; while @@fetch_status = 0 begin declare @query nvarchar(4000); set @query = N'insert into #results(row_id,field_name,oldval,newval) select d.row_id,@field_name,d.' + @field_name_sanitised + N',i.' + @field_name_sanitised + N' from #deleted d inner join ' + @TABLE_NAME + N' i on d.row_id = i.row_id where (d.' + @field_name_sanitised + N' <> i.' + @field_name_sanitised + N') or (case when d.' + @field_name_sanitised + N' is null then 1 else 0 end <> case when i.' + @field_name_sanitised + N' is null then 1 else 0 end);' ; exec sp_executesql @stmt = @query,@params = N'@field_name sysname',@field_name = @field_name ; fetch next from f into @field_name,@field_name_sanitised; end; close f; deallocate f; -- Do something meaningful to #results here
我如何访问#results?我必须使用光标吗?
解决方法
我们通过以下方式解决了这个问题.
select <list of tracked columns here> into #deleted from deleted; declare /*const*/ @TABLE_NAME sysname = '[table name]'; declare f cursor local forward_only read_only for select c.name,@field_name_sanitised; end; close f; deallocate f; -- Do something meaningful to #results here
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