How to segment account info and profile info?
Unless there is a security problem (you want someone to view some information, but not the other), there is no need to; however in many sql platforms you can deny access to specific fields in security or just create a view. The only other reason you would want to have two tables is if you have a business reason to segregate the data to two separate tables. Otherwise, if you are constantly needing to get information from table A and table B at the same time, you have to join each time which will add to overhead.