I.The stage of development about the database management
Artificial management stage、File management stage、database management
II.Database
1.Database Management System(DBMS): the data management software between user and operating system.
2.Database System(DBS): involve database、software、people、hardware
III.The model in data abstraction process
conceptual model、data model、physical model
IV.Three essential elements of data model
1.data structure、data operation、integrity constraint
2.The commonly used data model
hierarchical model(tree structure)、network model(graph structure)、relation model(two-dimensional table)、object oriented data model、object relation data model、semistructure data model
Father of relation database:E.F.Codd
V.Three-level schema structure of database system
Schema(logical schema):one database one schema.
External schema(subschema):the subset of schema, one schema many subschemas.
Internal schema(storage schema):one database one internal schema.
Two-level image realization:external schema/schema image、schema/internal schema image