Views provide added convenience to access protection.
The principle on which views are based is that groups of users are only shown the information that they need.
In combination with privilege-based access protection as described in
section “Access protection based on privileges in SQL”, views make it possible to ensure that individual groups of users only have access to the information that is intended for them. Through views and privileges SESAM/SQL provides flexible and comprehensive means of implementing data protection that meets both user's information requirements and data protection requirements.
For example, it might be desirable to create a view of a table containing data on all employees that only comprises the first name, surname and department columns. All employees can be given the SELECT privilege for this view. By contrast, the SELECT right for a second view that also includes other columns, such as salary, birth date, address, etc., should only be granted to a select circle of persons, such as personnel department staff. Restrictions should be even tighter in connection with the granting of rights to alter individual columns.
A further option would be to use department-specific views to limit to the SELECT privilege granted to all employees so that they can only ever view data pertaining to colleagues within their own departments. In this case one would grant a department-specific privilege for the relevant view.