CSV identity fields: nHibernate oddity or db design error?

Question

I've inherited a database and know an nHibernate engine was used on top of it.

Inside the database I see CSV values representing multiple identities instead of "proper" link tables being used for primary and foreign keys.

For example one tuple looks like this:

PersonID, int: 1
Name, varchar: John Smith
Edus, varchar: "76,5262,5261,5263,5264"
Events, varchar: "533,568,538,548,567,572"
Email, varchar: [email protected]

I'm curious if this is a feature of Hibernate (possibly a way to configure it) or just questionable relational database design?

Answer 1

Questionable database design.
This is called repeating groups.
It violates First Normal Form.

Answer 2

NHibernate does not directly support anything like that, so you'll have to look at the rest of the code.