suggest that you move the password to a separate table (my_role_password) with 2 columns:
my_role_id
password.
This way you can make the my_role table totally unalterable by the user, yet they can change their own password.
Actually, you should NOT be storing passwords in plain text, they should be stored as a secure hash (better than MD5).
I have no clue what you are trying to get at here...the core problem is with database defined roles - which are maintained in the system catalog - and the fact that marking a session read-only disallows updates to the system catalog...
I do not see how adding a user table with role and password overcomes that problem since the user table would be read-only too - so how would they still be able to change their password if the cannot alter the table (data alter, not structure).
