Replacing Oracle's FIRST_VALUE and LAST_VALUE analytical functions.
Hi,
I am using OBI 10.1.3.2.1 where, I guess, EVALUATE is not available. I would like to know alternatives, esp. to replace Oracle's FIRST_VALUE and LAST_VALUE analytical functions.
I want to track some changes. For example, there are four methods of travel - Air, Train, Road and Sea. Would like to know traveler's first method of traveling and the last method of traveling in an year. If both of them match then a certain action is taken. If they do not match, then another action is taken.
I tried as under.
1. Get Sequence ID for each travel within an year per traveler as Sequence_Id.
2. Get the Lowest Sequence ID (which should be 1) for travels within an year per traveler as Sequence_LId.
3. Get the Highest Sequence ID (which could be 1 or greater than 1) for travels within an year per traveler as Sequence_HId.
4. If Sequence ID = Lowest Sequence ID then display the method of travel as First Method of Travel.
5. If Sequence ID = Highest Sequence ID then display the method of travel as Latest Method of Travel.
6. If First Method of Travel = Latest Method of Travel then display Yes/No as Match.
The issue is cells could be blank in First Method of Travel and Last Method of Travel unless the traveler traveled only once in an year.
Using Oracle's FIRST_VALUE and LAST_VALUE analytical functions, I can get a result like
Traveler | Card Issue Date | Journey Date | Method | First Method of Travel | Last Method of Travel | Match?
ABC | 01/01/2000 | 04/04/2000 | Road | Road | Air | No
ABC | 01/01/2000 | 15/12/2000 | Air | Road | Air | No
XYZ | 01/01/2000 | 04/05/2000 | Train | Train | Train | Yes
XYZ | 01/01/2000 | 04/11/2000 | Train | Train | Train | Yes
Using OBI Answers, I am getting something like this.
Traveler | Card Issue Date | Journey Date | Method | First Method of Travel | Last Method of Travel | Match?
ABC | 01/01/2000 | 04/04/2000 | Road | Road | <BLANK> | No
ABC | 01/01/2000 | 15/12/2000 | Air | <BLANK> | Air | No
XYZ | 01/01/2000 | 04/05/2000 | Train | Train | <BLANK> | No
XYZ | 01/01/2000 | 04/11/2000 | Train | <BLANK> | Train | No
Above, for XYZ traveler the Match? clearly shows a wrong result (although somehow it's correct for traveler ABC).
Would appreciate if someone can guide me how to resolve the issue.
Many thanks,
Manoj.
Edited by: mandix on 27-Nov-2009 08:43
Edited by: mandix on 27-Nov-2009 08:47