The universe is occupied by objects: relatively stable configurations of matter. Objects have physical states, most of which are meaningless. A computer is composed of a large number of objects whose states we can manipulate. We use those otherwise meaningless states to represent data, concepts, and other objects.
These simple observations are at the core of the Concept and Object Modeling Notation, or COMN (pronounced “common”), a graphical notation for modeling data, software, and meaning. COMN is more fully described in the book NoSQL and SQL Data Modeling: Bringing Together Data, Software, and Semantics, by Ted Hills (Technics Publications, 2016). This page is your source for free resources that enable you to use COMN to design and describe data and software.
To keep up-to-date with COMN as it develops, follow Theodore Hills on LinkedIn. See below for training opportunities.
Reference and Stencil Downloads
COMN 1.1 Reference:
COMN 1.1 Stencil:
COMN 1.1 Reference Sheet contributed by Paul Rogers
White Papers
- No E-R: Why Modeling NoSQL Databases Must Go beyond Entity-Relationship Modeling, and How to Get There
- The Hybrid Data Model
- Cardinality, Optionality, and Unknown-ness
Theory
- Three-Valued Logic
- A Systematic Solution to Handling Unknown Data in Databases
- An Approach to Representing Non-Applicable Data in Relational Databases
Additional Resources
- Blogs by Ted on The Data Administration Newsletter (TDAN.com)









