Contexts and loops

building semantic layer
1

I have been fighting with a universe for some time now, I learned through searching the posts that half my problem was the use of shortcut joins to resolve loops ( I didn’t realize you could only have one per query). I am now trying to use contexts as I am seeing the use of alias’ causing a lot of confusion for the average user.

I am trying to create a Universe that combines two databases, one is an aggregation of another. After looking at the eFashion example and reading about contexts in the Designers PDF file multiple times I have come to the following conclusion:

Contexts will not work with my current structure because there are two separate unrelated paths requiring contexts and no common value to join them on in reports.

A brief example of the database is that I have a list of chains, stores, and customers on one side. On the other side I have different lists of products and groups of products I offer. With the way contexts work would I be able to create them where the separate queries would group(link) properly if I were to add a table showing the relationship of the stores with the products?

Cardholder_Redemptions Cardholder Chain Store
Offer Promotion Promotion_Product Product
(Aggregate table)

Listserv Archives (BOB member since 2002-06-25)

2

Hi Greg,
I also have decided against shortcut joins and contexts (I don’t want to have to put all my joins in contexts). I think contexts cause an equal or greater amount of confusion for the average user, forcing them to pick contexts they may not be familiar with, or that may not have anything to do with their job.
There are some tradeoffs in using aliases, but I’ve found them to work satisfactorily. The issue becomes the duplicate objects that you have to create. Where do you put them? I’ve organized my objects into logical classes, grouped according to a particular job function, or some other physical or logical relationship. In some universes, I’ve informed the users that once they enter the highest level class e.g., “Shipping”, they don’t need to look at anything in the other highest level classes e.g., “Customers” or “Orders”. Therefore, the fact that you have duplicated objects in the other classes doesn’t cause confusion with your users.
I hope this helps somewhat,
Roger Poole
rpoole@nswc.navy.mil

. . . Am I thinking along the correct lines here? Am I making things harder by avoiding alias'?

Thank You,
Greg

Listserv Archives (BOB member since 2002-06-25)