Table of Contents
The purpose of the app to be built is managing information about movies.
The app deals with just one object type:
Movie, as depicted in Figure 7.1 below. In the subsequent parts of the
tutorial, you will extend this simple app by adding actors and directors as further model
classes, and the associations between them.
In this model, the following constraints have been expressed:
Due to the fact that the
movieId attribute is declared to be the standard identifier of
Movie, it is mandatory and unique.
title attribute is mandatory, as indicated by its multiplicity expression , and has a
string length constraint
requiring its values to have at most 120 characters.
releaseDate attribute has an interval constraint: it must be greater than or equal to
Notice that the
attribute is not mandatory, but optional, as indicated by its
multiplicity expression [0..1]. In addition to the constraints described in this list, there are
the implicit range constraints defined by assigning the datatype