select * from sys.objects

declare @i int

select @@rowcount

use tempdb
go

--Creating the table
create table Demo (i int, j int, TimeUpdated datetime)
go

--Creating the trigger
create trigger DocumentUpdateTime
on Demo
for update, insert
as

--Doing an update without using varibles.
--More recommended because the update
--can effect many rows
update Demo
set TimeUpdated = getdate()
from Demo inner join Inserted
on Demo.i = Inserted.i and Demo.j = Inserted.j
go

insert into Demo (i, j)
select 1,1
union all
select 1,1
union all
select 1,2
go

update Demo set j = 4 where j = 2
go
waitfor delay '00:00:01'
update Demo set j = 3 where j = 1
go
--Notice that the value of TimeUpdated
select * from Demo

update Demo set j = 1

--Notice that again it modified the column
--TimeUpdated.  If I was using varibles,
--it would update some of the records
select * from Demo
go

drop table Demo