Addemar offers the possibility to manage your primary keys.
The functionality first need to be activated on your account by an Addemar Support person.
Once Activated, go to your segment section in the application
In the Segment section inside addemar, click on the Fieds to come into your fields section
When the option Manage Primary Keysis activated, you see this button on top of the section.
This button gives you a popup where you can manage the primary key.
Email is the standard primary key. If you change this you need to be aware that this has also some side effects*.
* When email isn't the primary field, you can upload the same email adresses more than once and if you deliver mails it can happen that the same email adres received several mails.