Overview of Data Model
The data model used on this site can be motivated by an example.
At the end of 2023, HarperCollins introduced a new blue cover design for Unfinished Tales as part of a whole series of matching “signature paperbacks” of the works of J.R.R. Tolkien.
The copyright page of the new edition:
- gives the copyright year of the text as 1980
- has an ISBN-13 of
978-0-261-10216-3 - states that it was “Published by HarperCollinsPublishers 2010”
- indicates that it is the 18th impression
Comparison with other issues of Unfinished Tales shows that each of these properties (along with the cover design) defines a different level of hierarchical grouping:
- “those with an ISBN-13 of
978-0-261-10216-3” are a superset of - “those published by HarperCollins in 2010” are a superset of
- “those with the new blue cover design”
The designation of “18th impression” is scoped to the “Published by HarperCollinsPublishers 2010” but there are other 18th impressions even with the same ISBN. The ISBN did not come into usage with the 2010 publication. It goes back to the first paperback edition from Grafton in 1991.
In order to model these properties, we need at least need the following levels:
- Publication Group (ISBN
978-0-261-10216-3— the regular paperbacks from 1991 on) - Publisher Edition (HarperCollins 2010 Paperback)
- Impression Group (impressions of above sharing signature blue cover design)
- Impression (18th impression within above Publisher Edition, although sometimes this does not restart at 1 with a new Publisher Edition)
This is how the information on this site is initially modelled: a Work and entities at each of these levels to which properties can be attached. We have not yet gathered enough information on pagination and minor text variations to know how these fit in yet. Nor is it entirely clear what triggers a new Publisher Edition and when it gets a new ISBN.
All of the data is currently represented as YAML files according to a particular schema.
Note that everything is still subject to change as we continue to add more data and work with descriptive bibliographers, metadata librarians, and collectors (especially the Tolkien Guide) as well as link the books data to other entities as part of the larger Tolkien Linked Open Data Project.