I'm designing an entity to represent a log-in object. The unique username value is an email address, that will go onto the username field.
Should I add a second field called email to indicate a contact email address for the user considering that it would be valued copied from the username field?
My requirements are email address as username, password, plus contact details such as first name, last name, email address.
When you came across a scenario like this, what did you choose to do?