Subtable for each user [duplicate]

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So i've been trying to make this programme that will store some data for each user (some simple strings). It has a login, registration and the main screen. I'm using sqlite DB, and i made one table for login and it all works fine. But what i can't figure out how to do is, how to create another "subtable" for each user when he/she registers ?!? What i want to make is, the main frame to list the each users own data. PS. On succesfull login, the login frame instatly populates the table in the main frame, where it's going to be possible for users to insert, delete or change data. Can anyone help me ?