I would like to make sure that there be only one record associating the same two records of my many-to-many association. My intuition is that it would not be possible to create a duplicate many-to-many record in the UI but I fear that through microflow, direct injection or api, it might happen. Is there a native default functionality to consider that the primary key of “implicit” many-to-many associations is always the conjunction of the two parents ids? If not, is there a way to impose this check wihout having to manually recreate the mtm association with an intermediary table? Thanks, Patrick
Mendix is already setting unique constraints on database level to ensure that there are no duplicates.
You can see it if you run your application locally on a postgresql database. Mendix is creating a table for each association. You will notice that there is a uniqueness constraint on a many to many association table.