List of Values is a powerful feature that allows users to select from a pick list when setting conditions in a query. This is especially important if you want to query on codes linked to a set of products. Using the List of Values feature, you will not need to memorize which codes go to which products.

The part that I would like to focus on is Cascading List of Values. In a real world Data warehouse for example, we may have thousands of customer codes. As a business user, in order to get to the customer codes I desire, I would probably want to select my customers from a certain region. Using Cascading List of Values, I can first select which regions I want to view and then select my customers from there.

Please note that it is important to think of the most efficient path a business user can take to get to their answer. One blunder that happens with many developers is the lack of planning when creating a Cascading List of Values. Some may include too many levels which in the long run increases the response time of user selection or too few levels which would cause users to spend too much time looking for certain values.

While working with many Universes, I’ve noticed that sometimes not enough attention is given to naming objects and the ordering of objects. This in turn may cause confusion with the business users since they are not completely clear on what each of the objects do.

Ordering of objects

When you have objects of the same class grouped together, it makes it much clearer to the business user to view when they see it in a hierarchal form instead of alphabetically. Lets take for example date objects. We have a year, quarter, month, and day object. The largest increment or grouping should always appear at the top and the most detailed at the bottom. Having this ordering will facilitate drilldowns. If these were sorted alphabetically, a business user would have to do more work in order to come up with a drilldown hierarchy.

In this article I would like to talk about Chasm traps and Fan traps. These are problems that we often experience while building universes and reports. When encountering these traps, one may wonder what is going on? How come my sum statements arent adding up correctly? Or why am I missing some rows? A properly designed universe will help avoid these problems. In addition, a good understanding about measures and contexts from report designers will help as well.

Chasm Traps

Let’s talk about Chasm traps first. In short, a Chasm trap can be imagined as a bottomless pit where some rows may unknowingly fall in and never come back out. So when viewing a report caught in a Chasm trap, one may ask “Hey where did Record X go??”.