Single session per user

Question

To demo my product, I put usernames and passwords right on the login page. I don't want people getting confused by the result when the same user is trying to do two different transactions, so I'd like to restrict each username to one session at a time. If someone tries to login with a username already in use, I need to reject their login.
Is there a way to do this?
Thanks.
Bill

Answer 1

Bill,
Better keep that PayPal account up-to-date. Sounds to me like you don't want SQL executed within any HTML DB session to be able to delete/update the same rows in tables or insert new rows when the timeframe between session creation and logout (or the final page visit of the session, e.g., user closes browser) overlaps with the similarly bounded timeframe of another HTML DB session.
HTML DB can't help you with this, there is no concept of an "active" session or "session in use".
You'd have to do something like insert a row into an ACCOUNT_IN_USE table when one of your accounts is "logged into", then delete the row when the logout takes place. Insert the row using a new process on the login page (raise error on dup key) and delete the row when the user clicks a logout link that should take them a logout confirmation page, which when submitted, deletes the row and redirects to the logout URL that you currently see in the Logout navbar icon. Replace the target of that navbar icon with a link to your new logout page. And then manually run a reset procedure to delete all the rows after so many users have not "actively" logged out but just closed their browsers and went home.
Scott