Updating only the last record.

Question

Hi,
I have a scenario where we get more than 1 record based on style. Everytime the new record comes in, I need to update the last record inserted. It requires a procedure to do it, but need some help on how to just update the last record only and not all the previous received records.
Here is the scenario.
create table test_1 as
with data_Set as
( select 'ABCD' style, 20080101 date_received, 2 duration,20080301 expire_Date from dual union all
select 'PQRS' style, 20080201 date_received, 2, 20080401 expire_Date from dual
) select * from data_set
so now on next run when i get another record
insert into test_1
select 'ABCD' style, 20080401 date_received, 3 duration,20080701 expire_Date from dual.
now the procedure should insert the incoming record and also update the expire_date for the previous record to a day before date_received for the new record. I am ok doing it when its only 2 records , but when i get another record of same style, i dont want to update all the previous received records. I only want to update the last record on file.
can anyone suggest?

Answer 1

STYLE     DATE_RECEIVED     DURATION     EXPIRE_DATE     SEQ_INSERTED
110427     7/31/2006     0     7/31/2006     2
110427     9/1/2007     12     9/1/2008     2
110427     8/2/2008     24     8/2/2010     3
468130     3/13/1997     0          2
468130     3/13/1997     12     3/13/1998     2
468130     1/12/2008     12     1/12/2009     3
Here is my data set
and here is the query i use to update, does it look correct?
update test b
set ( expire_Date) =
(select start_date - 1
from test a
where (style_no, date_received) in
(select style_no, max(date_received)
from test c
group by style_no
and a.style_no = b.style_no
and style_no in ('468130','110427')