Lost in joins

[wlandgraf (Wagner Landgraf)]

@Stickens_Didier

First question:
In order to get such a dataset, I thought I should define an entity that returns the data. But if I do this, a new table is created, which is not what I want.

You don't need to create your own class. In the majority of the cases, you will get the existing objects, and since they have associations, you get data from the other object (table) by reading the associated properties. For example, CategoryComponent.Component..Name will get the name of component from the CategoryComponent intermediate table.

@Stickens_Didier

Second question:
Can you help in how the joins should be defined? All the examples I found are always based on a one to many relationship (which is done automatically by Aurelius). But here, I need to go from a many to one (Category_Component to Component) back to a one to many (Component to Component Attribute).

For that you should simply use the ManyValuedAssociation attribute to map the other side of the association. This allows you to go from CCM_CATEGORY to CCM_CATEGORY_COMPONENT.

From TMS Data Modeler (which looks you are using), they are not created automatically, but you can enable them in specific tables in the mappings tab:

Mappings Tab

Additional references:

sample of M/D with webcore

You code seems to be generated by Data Modeler, so in this case you can ask Data Modeler to add the many-valued association in this section: [image] Select and check the Many-Valued Association you want to add to mapping and it will be generated. In the case of your mapping, you have this: [ManyValuedAssociation([TAssociationProp.Lazy], CascadeTypeAllRemoveOrphan)] FDOC_MOV_MAG_R: Proxy<TList<TDOC_MOV_MAG_R>>; function Get_DOC_MOV_MAG_R: TList<TDOC_MOV_MAG_R>; But then in your m…