Table visual showing records that shouldn't be there

[dieterbe_vdb]

Hello, I have a data model with three tables: Parent, Child (link to Parent via e one to many relation) and Grandchild (linked to Child via a one to many  relation).

Parent table:

Child table:

Grandchild table: 

I want to visualize all combinations of Parents and Childs + number of GrandChilds (from the perspective of the Parent).
Measure I'm using: 

#Grandchild = COUNTROWS(tblGrandChild) + 0
I've added the + 0 as I also want to show the Parent/Child combinations who don't have a grandchild.



I notice that this works, however, in my visual (a Table) I also see Parent/Child combinations which aren't possible?  How come that in this case the relation between Parent and Child doesn't "work" => parent A isn't linked with child B and C so why is this combination shown?

How can that for example

[amitchandak]

@dieterbe_vdb , Using power query merge add parent Id to Grandchild  table and then join it with parent and child directly, then +0 should work better

Merge: https://radacad.com/append-vs-merge-in-power-bi-and-power-query

Should be very similar to Power BI Items/Categories not sold to the customers: https://youtu.be/AbuKvAnicwo

[dieterbe_vdb]

Many thanks for your answer!

I agree that joining tables will do the job.

My question remains: why isn't the relationship / filter working in my example => so why does PowerBI shows combinations which aren't possible at all? It is known (from the relations) that child BA can't be a child of parent A => how can I avoid Power BI to show this combination in my table (supposing that I'm working with different tables and relationships between these tables)?