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Database Environment - Coggle Diagram

- - - - (2) a manipulative part,
      - (1) a structural part,
      - (3) a set of integrity constraints,
  - - - Functional
      - Entity-Relationship (ER)
      - Semantic
      - Object-oriented
- - - - The external view includes only those entities, attributes, and relationships in the “real world” that the user is interested in
    - - physical implementation of the database
    - - The external view includes only those entities, attributes, and relationships in the “real world” that the user is interested in
  - - - Physical data
        independence
        
        The immunity of the conceptual schema to changes in the
        internal schema
      - Logical data
        independence
        
        The immunity of the external schemas to changes in the
        conceptual schema
- - - - A language that allows the DBA or user to describe and name the entities,
    - - A language that provides a set of operations to support the basic data
        
        Data manipulation operations usually include
        
        • insertion of new data
        
        • deletion of data
        
        • modification of data
        
        • retrieval of data
      - We can distinguish between two types of DML
        
        Procedural DMLs
        
        A language that allows the user to tell the system what data is
        needed and exactly how to retrieve the data.
        
        Nonprocedural DMLs
        
        A language that allows the user to state what data is needed
        rather than how it is to be retrieved.
  - - - • speciality languages,
      - • application generators
      - • presentation languages,
      - • very high-level languages t