Is it possible to use .DescendantsInclusive to define a data buffer in a Finance Business Rule? This is needed to clear data from legacy accounts that are no longer needed. For example: Dim myDataBuffer As DataBuffer = api.Data.GetDataBufferUsingFo

Answer

There is a knowledge base article (KB0011011) entitled "How to Clear the Data Cells in a Specific Data Buffer" that may assist in this.
Because OneStream stores data only against the base members in the Account dimension, there is no need to clear for all Descendants.

Source: Office Hours 2020-10-22 Partner Enablement