1. When a user is defined, a password is assigned to him. To be able to work with a database, a combination of user name and password known to the database must be specified.
2. The user is given access to the database if the combination of user name and password is valid. The user opens a session and the first transaction.
A user can only work with the database within a session. A session is terminated explicitly by the user.
3. The user name specified in order to get access to the database is called the 'current user' if the user is not a member of a usergroup. If the user is a member of a usergroup, then the name of the usergroup is called the 'current user'.