Effective date and expiry date is data warehousing

Question

I am new to OWB. I would like to know how we update expiry dates in slowly changing dimension tables by using OWB. Suppose if my source data is as follows:
Emplid Job Action Eff. Date
1000 "New Hire" 24-JUN-1999
1000 "Promotion" 27-SEP-2000
1000 "Merit" 01-JAN-2001
I would like to populate my target table like this.
Emplid Job Action Eff. Date Expiry Date
1000 "New Hire" 24-JUN-1999 26-SEP-2000
1000 "Promotion" 27-SEP-2000 31-DEC-2000
1000 "Merit" 01-JAN-2001 31-DEC-9999
I tried to read the source system rows in the order of emplid and eff. date desc. I wanted to pass eff. date of current row to the next row in the source system. In this way, I can easily determine expiry date of current transaction. I have a hard time to do this in OWB. I would like to know
1) Whether it is possible or not by simple mapping.
OR
2) Do I have to write any post mapping procedure?
OR
3) Is there any better way?
Your input is greatly appreciated.

Answer 1

Hi ,
follow these steps.
1) take the table, and again take same table,and join it on primary keys like say table a,table a1.
a.id = a1.id(+)and
a.start_date = a1.start_date(+).
2) take outputs of join in sort operator and sort a.id asc and a.start_date asc.
3) take o/p of sort operator in aggegrator.
4) take in the input of agg , a.id,a.start_date , and b.start_date,and group by a.id and a.start_date.
5) in output parameters add id and assigned id to it,start_date = a.start_date and create min_date = min(b.start_date)
6) then drag o/p to exp ,and create o/p parameets like id ,start_date,and end dates.
assign id to id,start_date = a.start_date and end date = if min_date is not null then mindate else
to_date('31-dec-4719')
and then get them in target table.
i have implemented this on my side,for any help pls feel free to get in touch.
Sharad.