With an aggregate, can be done something like this, being "product" the entity to display in the chart:
use the entity twice in the aggregate, and join them with the "with" operator and the condition
"Product.Id = NullIdentifier() or Product_2.Id = NullIdentifier()"
Create then the attributes to be used :



As you can see one instance from the entity is used to obtain one column value and the other instance to the other column value, the column used is identified in the DataSeries attribute .
This attributes can be used to sort the result list .
Well , that's other option.
Stay safe
Graça