Hi Adria,
you're right - this is an example of the hierarchy support in SAP HANA and if I'm not mistaken the example is taken out of the HA300 training course (right? at least it was the last time I presented the course).
Unfortunately the syntax for hierarchies is not yet officially released.
For your requirement, it might be possible to use this feature (not sure about the SAP business one data model, so I cannot comment on this).
However, using a SQLscript approach is definitively feasible here as you can create recursion with that.
- Lars