Now I have one devise model, which uses email as authentication_key.
I want to add one new devise model, which uses student_id as authentication_key.
Some guide tells me to modify the configuration
"config.authentication_keys = [ :email ]" by replacing the :email with :student_id.
After modification, the first model login always fails, so I think I have to indicate different authentication_keys for the two models separately.
How should I do?