##
Data Modelling, Entity Modelling and Logic

This chapter contains a scattering of further thoughts on data modelling, entity modelling
and logic.
On the importance of questions of commutativity to how data is represented

Starting with a mediation on everything data:
This next section is under developed at the moment but the point is that it is natural
to model in ER what ER is and this is the ER meta model. This evolves as more concepts
such as commutative diagrams are added. At the moment what we have here is a simple
version.
This example shows how a category theory perspective informs
physical data modelling:
The next section comprises notes on the different ways that ordinal numbers can be
represented in entity modelling and of the constructions that follow on from them.
These are thoughts towards foundations rather than being of practical value at the
moment.
Two papers that I have recently drafted on the concept of relationship scope and its
use in
relational data design:
How dependent types may be modelled: