Grammatical data base model

摘要

A model for describing the data base at the conceptual (logical) level is presented. The philosophy underlying the model is based on the concepts of entity, descriptor, property association and relationship. The model includes a temporal dimension as a fundamental component. Both the data base and its logical schema are related to time. The logical schema, which also contains the constraints for the integrity of the data base, is regarded as a data base itself. A data base is regarded as a collection of statements in a specific Assertion Expression Language. The grammar of this language and the role of the logical schema as part of this grammar are discussed.