How can I disable a registration if a value is duplicated?

How can I disable a registration if a value is duplicated?

by Plataforma Aula Virtual -
Number of replies: 0

Hi! 

I'm administrating a Moodle site in which many students have two accounts. Those students can't have the same email, since the system won't allow that in the registration form.

The registration form allows students to create an account with the same student's identity document which is duplicated in this cases I'm describing. How can I deny the form submission if the student's identity document number is already in the database for another student?

Thanks!

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