I imported 8500+ external users from an external user table using Feeds module successfully. Now, I am trying to add some more attributes to these users (ie. age, gender, ...). I proceeded to create several new fields for my users under admin/configuration/account settings/manage fields (ie. Age, Gender, ...). However, these fields are now all empty and it would not be possible for me to manually edit these fields for all users.
Could someone please tell me where D7 stores these new fields in the database (which table)? I would like to use a SQL script to automatically update the users with these fields.
PS. Is using a SQL script to update these information the correct approach?