Lookup field not filled in child entity inside Data Structure

I was trying to …

  1. I have a Data structure with two entities (parent, child).
  2. I want to pass data from parent entity’s lookup field to child entity to filter values in Combo-box
  3. I put Parent entity’s field to child entity to make the value available in the child entity
    obrazek

I was expecting …

The value will be filled in by the value from the parent entity.

Instead I’ve got …

The value is empty.

obrazek

Notes

  1. When I create function field in the parent entity which I fill with function isnull(myLookupfield, '_guid_empty'), then the value is passed into child entity correctly. I would expect the same behaviour for the lookup field directly.

obrazek