Entity-media modelling: Conceptual modelling for multimedia database design

This paper presents a conceptual modelling methodology and diagramming notation for designing multimedia databases. Entity-media modelling (EMM) ensures that all information contained in a media artefact - technical properties, semantic content, and context of use - is modelled early in the design process and preserved through to implementation. The key construct in the modelling process is the media entity, used to denote both the physical media artefacts and the roles they play within the database. The media entity is represented schematically in the ERD+, a notation based on the entity-relationship diagram (ERD). The use of the media entity and the ERD+ permits the modelling of the semantic role and technical requirements of the media artefacts, in the multimedia database in parallel with the data component. The completed ERD+ translates into a conventional ERD for implementation in the preferred database system.