What is the best approach to handle multiple FK with single table.

Question

If two tables are joined with each other with more than one ways, for example
MAIN table is (col1, col2,....coln, person_creator_id, person_modifier_id)
PERSON table is (person_id, name, address,........ phone) etc
At database level PERSON_CREATOR_FK and PERSON_MODIFIER_FK are defined.
Objective is to create a report that shows
col1, col2...coln, person creator name, person modifier name
If above two objects are imported with FKs in a EUL and discoverer plus is used to create above report. On first inclusion of person name discoverer plus will ask you to pick the join (provided the checkbox to disable this feature is not checked). Once you pick 'person creator' join it will never allow you to pick person modifier name.
One solution is two create a custom folder with query like
select col1, col2,...coln,
pc.name, pc.address,.... pc.phone
pm.name, pm.address,.... pm.phone
from main m,
person pc,
person pm
where m.person_id_creator = pc.person_id
and m.person_id_modifier = pm.person_id
Second solution is to import the PERSON folder twice in EUL (optionally named one as perosn_creator and other as person_modifier) and manually define one join per table. i.e. join MAIN with PERSON_CREATOR on person_creator_fk and join MAIN with PERSON_MODIFIER table using person_modifier_fk.
Now discoverer plus will let you drag Name from each person folder without needing to resolve multiple joins.
Question is, what approach is better OR is there a better way?
With solution 1 you will not be able to use functions on folder items.
With solution 2 there is a EUL design overhead of including same object multiple times and then manually defining all join (or deleting unwanted joins), and this could be a problem when you have person_modifier and person_creator in nearly all tables. It could be more complicated if person table is further linked other tables and users want to see that information too. (for instance, if person address is stored in LOCATION table joined with location_id and user want to see both creator address and modifier address....now you will have to create multiple LOCATION folders).
A third solution could be to register a function in discoverer that return person name when person_id is passed. This will work perfectly for above requirement but a down side is the report will run slower if they need filters on person names (then function will be used in where clause). Also, this solution is very specific to above scenario, it will not work if you want the report developer the freedom to pick any attribute from person table (lets say, person table contain 50 attributes then its not a good idea to register 50 functions).
Any comments/suggestion will be appreciated.
thanks

Answer 1

Hi
In a roundabout way you have really answered your own question :-)
In my opinion, the best approach, although by all means not the only approach - see below) would be to have the object loaded as two folders with one join going to the first folder and the second join to the other folder. You would of course name the folders appropriately.
Here's a workflow that I use all of the time and one that I teach when I'm giving Discoverer Administrator training. It might help you:
1. Bring in the PERSON folder to begin with
2. Make all necessary adjustments to bring it up to deployment standard. These adjustments would be: folder name (E.g PERSON_CREATOR), item names, item placement, default positions, default aggregation and so on.
3. Create or assign the required lists of values
4. Create any required calculations
5. Create any required conditions
6. Create the first join from this folder to MAIN.
7. Click on the heading for the folder and press CTRL-C.
8. Click on the heading for the business area and press CTRL-V. A second copy of the folder, complete with all of the adjustments you made earlier will be inserted into the business area.
Note: joins are not copied, everything else is.
9. Rename this folder to say PERSON_MODIFIED
10. Rename the items as appropriate
11. Add a join from this folder to MAIN - you're done
Other ideas that I have used and work well would be to use a database view or create a complex folder. Either will work, In both cases you would need to join on some other column other than the ones you referred earlier.
I hope this helps
Best wishes
Michael