Securing hierarchies using PATH functions

In most organizations, data is not directly related to a single user who has access to it. Instead, there is a group of people that each have access to different sets of data. Managers have access to the data of employees reporting to them, for instance. DAX contains a set of functions to deal with parent-child hierarchies like these: the PATH functions.

Hierarchical tables

First, let's take a look at a typical organization structure, in this case, that of QuantoBikes, our example company. QuantoBikes is organized into several divisions aligned with continents, and each division consists of multiple teams.

The organization map is pictured below:

Figure 2.1.17: QuantoBikes organization map

In the Employee table, this organizational hierarchy is registered by having a column called MngrNr, or Manager Number. This column contains the employee number for each employee's direct manager; only the CEO does...