Gantt, show Tasks without data

Thanks Idrissshatila. I will try this but I might have further problems.

I have three tables; Customers, Orderdata and Resources.

All three tables are connected through the value Company. I have field resources in both Orderdata and Resources. In Orderdata, resources are applied to every order. In Resources I have the complete list with Resources. When applying fields to resources within table Orderdata everything looks fine but if I apply a field from table Orderdata to the resources in table Resources I get the same aggregated value for every resource. Maybe there is a problem with my relationsships? Any clues?