Many to many relations in natural hierarchies
This blog entry is about a problem with attribute relations that can appear when you migrate cubes from AS2000 or have issues whith many to many relations in natural hierarchies. Natural hierarchies can only have one-to-many or one-to-one relations from a parent to the next lower level. The problem is that you can have many-to-many relations, a child level points to more than one parent on the next level, since this is not detected by primary key constraints and this problem occur above the primary key. If this was the case in AS2000 the engine will put its own unique keys for children that points to more than one parent. In SSAS2005 this unique key creation is not present and I will show an example of this here.
You will have to create the same cube as used in the previous blog post. This example will carry on from where we ended previously.
Tags: design, many-to-many