Array of array

How to display business object that has multiples of another business object as attributs in a table widget?

Hey, everyone, I'm relatively new to Bonitasoft (Community-7.8.2). So, sorry if this question seems dumb.

I've been having trouble getting attributes to be displayed in a table widget.
My business object "Analyse" contains multiples of this other business object called "DemandeAnalyste" in a composition relationship.
From my understanding, this makes the BO "Analyse" I'm trying to populate the table with an array of array and that's why my attempt has failed.