One of the first things you are told about Cassandra is the importance of Data model, however, we are rarely given a apples-to-apples real world example of the impact of data model on Cassandra. In this discussion, we will present a real world example of an existing data model that we are actively replacing. Our initial data model was one with millions of rows per node, but only a small amount of sparse data per row. In refactoring, we encoded the same data set into a much smaller number of rows, each of which was much wider (a "square" table layout, versus our original row-heavy "rectangular" layout). We will present the details of the current and new implementation, the unexpected challenges we encountered when comparing the models, and our measured results.