validating is_unique property for custom attribute in customer registration form

Question

I've followed this answer@stackexchange to create a new attribute (called mobile) for the customer entity.

I was able to create an input field in the registration form(customer_account_create) and able to save the entered value in customer_entity_varchar table associated with the attribute_id (mobile)

Now, I wanted like to make this attribute unique i.e no user can register for another account using same mobile number. To achieve this, I modified the msql4-install-0.1.0.php file at (app/code/local/MyCompany/MyModule/sql/customerattribute_setup/...php)

<?php
$installer = $this;
$installer->startSetup();

$installer->addAttribute("customer", "mobile",  array(
    ....
    "unique"     => true,
    ...

    ));

By changing the property from false to true. The new customer attribute has is_unique=1 in the eav_attribute table.

However, the unique constrain does not apply for some reason when I try to create a new user from the registration form using different email ID but same mobile number (associated to attribute - mobile).

Do I have to do something else so that I can allow users creation only if the said attribute is not associated to any other user ??

Answer 1

The customer attributes has no is_unique option which is available for product attributes