#databases #semester3

Reference #

Oracle Docs W3Schools Reference

Characteristics of Database Approach #

• Main Characteristics of Database Approach
  1. Self Describing nature of a DB System [ Catalog of the Data ]
     • it contains the DB and Metadata
     • The DB Catalog is Used by
       • DBMS Software
       • DB Users

     Comparision with Traditional File Processing (TFP) #

      TFP can only access specific DBs
     

     1. Insulation between program and data abstraction
        • Program Data Independence - structure of the data files is stored in dbms catalog separatey from access programs
        • VS TFP Any Change to the Structure should be reflect in the corresponding programs
     2. Program operation Independence
        • In DDDBMS and ORDBMS users can define operations on data as part of DB Definitions
        • an operation is specified in two parts
        • implementation of the operation is specified separately and can be changed without affecting the instance
     3. Data Abstraction
        • Allows program data independence and Program Operation Independence
        • It provides users with conceptual representation of data
        • Supports Multiple Views of Data
     4. Supports Multiuser Transaction Processing
        • Multiuser DBMS
        • Concorrency Control Software
        • Online Transaction Processing Application