MatBase is a prototype intelligent data and knowledge base management system based on the Relational, Entity-Relationship, and (Elementary) Mathematical Data Models, having two current
versions (MS SQL Server and C#, MS Access and VBA). Users may work with it only at one or
any combination of these conceptual levels, without any programming knowledge (be it SQL, C#,
VBA, etc.), to create, populate, update, and delete databases and corresponding management
software applications. The paper introduces the MatBase architecture and the principles used to
transparently program while modelling data at these three conceptual levels with this tool. A real-life example illustrates them.