I have a members table with usernames (not SQL accounts). Each of the tables have a "edited username" column which contains the username of the last user who modified the row.
In my application layer, I authenticate the user and put the username into a session. When I call the stored procedure, is there anyway for it to detect which user is calling the stored procedure WITHOUT passing it in as a parameter?
I don't believe so... if you're application is connecting with it's own credentials then the only way for the stored procedure to know who's calling it is to pass in the username from the session variables.