Relations refer to foreign keys from the database. Additionally to foreign keys, it is possible to create virtual foreign keys that do not represent a real object from the database but will act as such in Asmidio RDG.
The relations page lists all database foreign keys and user-defined foreign keys. If foreign keys are missing,
it may be necessary to refresh the database metadata (shortcut
Relations are used to generate values for foreign columns, i.e. columns that reference another through a foreign key. Two parameters can be configured: the minimum cardianlity, and the maxiumum cardinality. They represent the minimum and maximum number of times a primary column may be refered to, in the foreign column.