Because student course enrollment is so central to what we do, it should be no surprise that this is an area where complications arise in our data. The complications have to do with the fact that many tables are joined together, resulting in multiple paths between some tables.
Branches help address the complications.
Tables of data such as are in the Warehouse have associations with each other called relationships. Tables with a relationship have one or more columns shared in common. To look at data in these two tables at the same time requires that we use a join, which is a condition that limits our query results to rows with matching values in the shared columns. The same is true of getting from one table to another. To get from one city to another requires selecting a path along the roads.