Entity Modelling

www.entitymodelling.org - entity modelling introduced from first principles - relational database design theory and practice - dependent type theory

On the hierarchical and relational representations of data

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. Data storage - a modern model of an ancient data system - I stumbled across this model on the internet and was fascinated by it: 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: