Basic Database Design -

This question will be a little childish, I have three tables, users, user groups and contacts. In my system, the end user is a Contact can be made and later it can define the visibility of the contact only for that user, or for a group of users or through the set of usergroups, so I am thinking about how my database will be designed, this user and Should be a lot between the contacts must be among the many many people between user groups and contacts. Certainly there are many relationships between users and user groups.

Thanks Thirin

If you have a set of users or set of user groups There is a possibility to determine the visibility, both of you have been mentioned, the M2M table. One contact_users and one contact_surgeorg

What I said is true if the "user's set" is different from the single "usergroup".