CMDBuild Forum

Domain class N:N seems not working

Hi Support,
I am trying to setup class relationship (N:N). I have 2 clasesses: Class_A & Class_B. The domain is setup as follows: Origin: Class_A; Destination: Class_B; Cardinality: N:N. Wehn I go to create a new attibute on either Class_B or Class_A by using type=REFERENCE I am not able to select the created DOMAIN (It does not show up). What am I doing wrong?
Thank you,
P.

It is not possible to create a reference attribute on an N:M relationship, it can only be done on 1:N or N:1 relationships. The same thing normally happens in an E-R model of a relational database, in which it is possible to create a foreign key only on 1:N relations.

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