Setting a condition for a 'has many' relation

By Hans de Groot , Created 17-DEC-2018, last editted 17-DEC-2018

I tried to add a condition in a relation that relates employees to an organisation.

I've added a condition to it, which filters only employees that are still active/employed.

Then I added a number expression to the organisation table with calculates the number of active employees like: count(var:record.activepositions)

It does not seem to work as I expected. It allways stays 0.

What am I doing wrong here or do I misinterpret the use of condition here?

I tried to add a condition in a relation that relates employees to an organisation.
I've added a condition to it, which filters only employees that are still active/employed.
Then I added a number expression to the organisation table with calculates the number of active employees like: count(var:record.activepositions)
It does not seem to work as I expected. It allways stays 0. 
What am I doing wrong here or do I misinterpret the use of condition here?