..  include:: /Includes.rst.txt

..  _data-model:

==========
Data model
==========

This extension does not provide a fully rounded data model but a set of service
classes. A ``Location`` may be organised hierarchically to model, for example,
world regions, countries, regions, cities, and buildings. A ``Period`` may
similarly be arranged in a hierarchy to model historical periods, phases, or
dates. ``Actor`` objects, on the other hand, may be grouped together via
``Tag`` labels, but otherwise stand on their own. They may refer to
organisations, individuals, or other entities in the sense of actor-network
theory.

In addition, the model provides flexible ``Tag`` objects to group other
classes, ``Relation`` objects connect classes with qualifications like the role
of an ``Actor``, and ``SameAs`` classes to connect entities to authority data.
Simple ``Keyword`` objects may be used to interconnect labels.

..  _graphical-overview:

Graphical overview
==================

..  figure:: /Base/DataModel/DataModel.png
    :alt: Data model of the extension
    :target: ../../_images/DataModel.png
    :class: with-shadow

    Overview of the extension's data model. Check the :ref:`api-reference`
    for further details.