The Principles and the Conceptual Architecture of the Metagraph Storage System

This paper discusses an approach for active metagraph model storage. The formal definition of the metagraph data model is proposed. The example of data metagraph model is given. The formal definition of the metagraph function and rule agents are discussed. The example of a metagraph rule agent is given. It is shown that the distinguishing feature of the metagraph agent is its homoiconicity which means that it can be a data structure for itself. Thus, the metagraph agent can change both data metagraph fragments and the structure of other metagraph agents. The definition of active metagraph is given. The possible states of active metagraph elements and transitions between them are discussed. The conceptual architecture of the metagraph storage system based on active metagraph is proposed. The approaches for mapping the metagraph model to the flat graph, document-oriented, and relational data models are proposed. The experiments result for storing the metagraph model in different databases are given. It is shown that the flat graph model is most suitable for metagraph storage.