Hierarchical structure also can be described in terms of generations and levels. Dimension members on the same layer of the dimensional hierarchy are referred to collectively as generations or levels. The relationships are defined as follows:
Generations—Counted down from the highest ancestor. The root member, or dimension name, is Generation 1. In the following figure, Market is Generation 1
Levels—Counted from bottom to top: Level 0, Level 1, Level 2, and so on. In the following figure, days are at Level 0
Leaf nodes—Lowest points in a hierarchy
| Number | Name |
|---|---|
| 1 | Ancestor |
| 2 | Parent |
| 3 | Child |
| 4 | Descendent |