facebook has about 500 million active user mean facebook maintain large information in their databases.
i want to know that:first question-----------
how they structured their database?
it logged in any user in just a second ( they take less time then other social network like orkut etc.)
i have a database table which has some coloms like id, username password, email etc.
now i have only 55 registered users (55 entries)
i want to know that what will happen if i have 100 million entries in same table?
will it work fine?