Hi! First of all, we do NOT recommend using this program for sensitive information, such as your real data, as this is just a test, we can't guarantee the safety of the database.
The program was made with the idea of storing passwords associated with emails, but you don't necessarily have to use it in that way. You can save another kind of accounts, like those programs who are username-based.
You can't enter the same id twice, and the program shouldn't let you, so if you want to add the same username again you should add another character at the end of the account id.
The program can:
    Add an account to the database, but you can't add the same username/email twice. For example, if you added the username "XDD", the program won't let you use that username again, so you should enter something like "XDD2" or "XDDD". The password will be asociated to the username you entered.
    Remove an account, the program will only ask you to enter which account you want to delete.
    Search an account to the database, this function will search the account you are looking for in the database and copy the password to your clipboard.