Custom Analytical Queries / CDS - Deriviation Functions

[jsur]

Hi,

im trying to understand the concept of deriviation functions in the context of custom analytical queries and cds views. 

My Goal is to understand and create deriviation functions for specific analytical query fields

As shown below, i want to create a simple Derviation Function for the field DeriviationPlaneType

I proceeded as follows (i tried to use the deriviation for CostCenter (ZF_MYCOSTCENTER) as an template):
1. My Base CDS Entity

2. My Deriviation CDS-Entity, my goal is to only have planetypes with the value '747-400'

This CDS-Entity is released (C1)

3. My Primary Data Source, as far as i understand, i need to associate the cds-entity which contains the field with the deriviation function (ZI_PLANETYPE -> ZF_MYPLANETYPE-> DeriviationPlaneType)

4. Custom CDS-View

5. Custom Analytical Query

I've created a custom analytical query based on the beforementioned custom cds-view.

But my Deriviation Function is not showing up

Did i miss anything?

I also tried to just copy F_MYCOSTCENTER

and creating a simple Cube

But i am getting an error message when using this cube in a custom analytica query when selecting my deriviation function.

I hope anyone can help me to fix this and to get an better understanding how deriviation function work.

best regards

Jonas