Intra-system relations
The third and final aspect of data models are intra-system relations. These are relations between the collected data tables of the system. In other words, they relate the system's Data tables based on the Keys you've specified for those tables.
Intra-system relations can be 1-N or N-N.
To get started, Specify intra-system relations.
Compare to Inter-system relations.
1-N intra-system relations
1-N relations are the most basic type of relation, from which N-N relations are derived. You must manually specify them in the NIM Studio, after keying your tables.
A 1-N relation means that for one (1) instance of entity X, there exists zero, one, or many (N) instances of entity Y. But for one instance of entity Y, there exists only zero or one instance of entity X.
N-N intra-system relations
NIM also supports N-N relations. Unlike 1-N relations, you don't manually specify N-N relations. Instead, NIM automatically calculates N-N relations based on your 1-N relations. You simply enable or disable them as needed.
A N-N relation means that for one (1) instance of entity X, there exist zero, one, or many (N) instances of entity Y; and for one (1) instance of entity Y, there exists zero, one, or many (N) instances of entity X. For example, an N-N relation can occur in a system where a group can have multiple users and a user can have multiple groups.
Strictly speaking, N-N relations don't add any functionality that is not already possible with 1-N relations. Instead, they reduce the number of necessary 1-N relations and simplify the use of filters.