How to create many to one relationship

Hello all,
I am trying to create a many to one relationship in my database connecting it using a User’s email, (which is the unique ID).

In essence a user should be able to have multiple items and items should have only one user. The issue I am having is creating an item with the email as the unique identifier. The only way I can set the email as the unique identifier for the item is to go into the wixdatabase and manually make it that way.

I am trying to connect the data bases and I don’t know how to get it to work with creating a new item.

Here is a picture of what my website roughly looks like. This is an item that a member should be able to add to their profile.

Does anyone have a solution or a tutorial that answers this question? Is wix going to make this a simpler process or produce a step by step tutorial?

Hi,
You can use reference field for that matter.

Good luck,
Tal.