Database Management System20805 marksData Models, Schemas, and Instances
Define data abstraction, data model, schemas, instances and database state.
Define data abstraction, data model, schemas, instances and database state. [5]
--- Data abstraction refers to the process of hiding the complexity of the internal details of how data is stored and maintained, and exposing only the relevant information to the users. A database system achieves this through three levels of abstraction: - Physical Level (Internal Schema): Descr...