Customize auth_user table and registration?

[DOMGA KOMGUEM RODRIGUE]

Hello all,

I'm a newby in web2py. So sorry if my problem cans be considered as obvious.

I'm working now on a project. In this project, i define a table custumer which references the auth_user table in a One-To-One relation as follow.

db.define_table('custumer',
                Field('custumer_code', 'string'),
                Field('parent', 'reference custumer'),   
                Field('user_id', 'reference auth_user', label = 'Utilisateur : '),   
                Field('created_by', 'integer', writable=False, readable=False),
                Field('created_on', 'integer', writable=False, readable=False),
                Field('modified_by', 'integer', writable=False, readable=False),
                Field('modified_on', 'integer', writable=False, readable=False)
                )

How can i customize the registration form in order to insert row in the two tables (auth_user and custumer) using data from a single form.

Thank you in advance for your response.

DOMGA