Универсальный логирующий триггер

alter trigger [dbo].[trigername] on [dbo].[tablename]
after insert,update, delete
as
 
--@@@@@@ insert @@@@@@@
if exists (select top 1 * from inserted) and not exists (select top 1 * from deleted)
begin
insert into [logs].[tablename] ([changes], [type], changedate, userlogin)
  values 
  (
    (select * from inserted for xml path('template')),
    'insert',
    getdate(),
    (select top 1 modifylogin from inserted)
  )
end
 
--@@@@@@ update @@@@@@@
if exists (select top 1 * from inserted)
    begin
        declare @columnname nvarchar(255)
        declare @sql nvarchar(500)
        declare @result xml
        declare @login varchar(50)
        declare @changes table 
        (
            [itemid] int,
            [сolumn] varchar(max), 
            [oldvalue] varchar(max), 
            [newvalue] varchar(max)
        )
 
         declare columnscursor cursor local for
            select column_name from information_schema.columns where table_name = 'tablename'
 
        open columnscursor
        fetch next from columnscursor into @columnname
 
        if object_id('tempdb..#inserted') is not null drop table #inserted
        if object_id('tempdb..#deleted') is not null drop table #deleted
    
        select * into #inserted from inserted
        select * into #deleted from deleted
 
        select top 1 @login = modifylogin from #inserted;
 
        while @@fetch_status=0
        begin 
            set @sql= 
                'select i.itemid as [itemid]
                        ,''' + @columnname + ''' as [сolumn]
                        ,cast(d.' + @columnname + ' as varchar(max)) as [oldvalue]
                        ,cast(i.' + @columnname + ' as varchar(max)) as [newvalue]
                from #inserted i
                    left join #deleted d on i.itemid = d.inemid
                where cast(d.' + @columnname + ' as varchar(max)) != cast(i.' + @columnname + ' as varchar(max))'
 
            insert into @changes exec(@sql);
 
            fetch next from columnscursor into @columnname
        end
 
        if object_id('tempdb..#inserted') is not null drop table #inserted
        if object_id('tempdb..#deleted') is not null drop table #deleted
 
        close columnscursor
        deallocate columnscursor
 
        set @result = (select * from @changes for xml path('row'));
        if @result is not null
        begin
            insert into [logs].[tablename] ([changes], [type], changedate, userlogin)
                        values  (@result, 'update', getdate(), @login)
        end
    end
    --@@@@@@ delete @@@@@@@
else
    begin
     insert into [logs].[tablename] ([changes], [type], changedate, userlogin)
      values 
      (
        (select * from deleted for xml path('template')),
        'delete',
        getdate(),
        (select top 1 modifylogin from deleted)
      )
    end