I'm currently evaluating a potential new project that involves creating a DB for typical customer information (userid, pwd, first & last name, email, adress, telfnr ...). At this point, requirements are only roughly defined.

The customer DB is expected in the O(millions) of records. In order to calculate some back-of-the-envelope numbers for DB sizing and evaluate potential DB options & architectures, I'm looking for some de-facto standards for these kind of records. In particular, the std size of every field (first name, last name, address,...) or typical avg for a simple customer record would be great info.

With so many e-commerce websites out there, there should be some kind of typical config that can be reused and avoid re-inventing the wheel.

Any ideas?