The fundamental concepts in an application domain related to narratives (intended as stories about a specific topic) are: events, characters, objects and locations. Some of the facts that characterise this domain can be stated as follows:
- A narrative is composed of one or more events.
- A narrative is composed exclusively of events.
- Each event occurs in exactly one location and has exactly one beginning and one ending, both represented as a datetime using the appropriate XSD datatype.
- A character can be human or not human.
- Each location can be a real location or a fictional location.
- Each character, each location and each object have a name (a string).
- Each event has at least one participating character or object.
- Each narrative is created by at least one narrator.
- The narrator has at least one contract with a publisher.
- A book reports one or more narratives.
- A book has a title (a string) and it is identified by an ISBN code (a string).
- A book has exactly one publisher (that is an organisation). The publisher is identified by a name (a string) and an ID (a positive integer).
- A publisher publishes more than one book.
- A book has exactly one price (a positive integer).
- The publisher sells the books through more than one bookshop.