Chapter 16. Multi-Path and Ragged Hierarchies

This chapter discusses the multi-path hierarchy, expanding on the single-path hierarchy you learned in Chapter 15, “Dimension Hierarchies.” You might recall from Chapter 15, the month dimension in our data warehouse has one hierarchy path, the year-quarter-month path. In this chapter we will add a new level, campaign session, and add a new hierarchy path of year-campaign-month. The month dimension will then have two hierarchy paths and therefore has a multi-path hierarchy.

Another topic of discussion in this chapter is the ragged hierarchy, which is a hierarchy that does not have data in one or more of its levels.