A view is an object that selects, transforms, permutes the data from another object, called its database, and also is editable in that it can be used to change the underlying database. It is like a database view except that it is editable and defined for objects rather than relational databases. Database views can themselves be databases for other views, so we can have cascaded views. Example of database, view pairs: budget/sorted budget, complete budget/direct costs,
A database provides the same interface as a model. In addition, it is associated with ``aspects'', which can be considered sets of fields. It is also an observable, and can send messages to observers.
A view is an observer.
In addition,
it should probably indicate which aspects of its database it is dependent on.