Question

I am creating a site where each registered user can store a list of contacts. It occurred to me that rather than storing the contacts in a table with user_id, contact_name, contact_email, it would be better to normalize it to prevent the same names/emails being stored multiple times. As a result, I now have 4 tables: users, names, emails and contacts where contacts contains user_id, name_id and email_id. Am I heading in the right direction, or am I complicating things needlessly?

Thanks for all the helpful responses to what I can see now is a pretty nebulous question. It may be a good idea to explain my reasoning.
In an example scenario, where there are 100 users, most of whom have joined though the recommendation of another user, there will be a large number of common email addresses shared by each users contact lists. However, [e-mail], may be known as John, J Smith, Johnny boy etc. by different users. If I understand the principles of normalization correctly (unlikely) the separation of user, contact name, and email address in to separate tables, should reduce duplicate entries significantly and make the database more efficient. In the example below, the Contacts table could contain the same email addresses multiple times.
So, to cut a long story short, is it better to have more entries than necessary in one table or several smaller tables without duplicate entries?

Answer 1

You’re probably needlessly complicating things: I’d recommend one table for users, one for contacts and a join table to allow a many to many relationship between the two. If contacts are not shared between users it’d be acceptable to have the user id as a foreign key in the contacts table.

Hope this helps