File Processing
Each user defines and implements the files needed for a specific application
Redundancy in defining & storing data
Database Approach
A single repository of data
-Self-describing nature of a database system: A DBMS catalog stores the description of the database. The description is called meta-data . This allows the DBMS software to work with different databases. catalog: structure of each file, type & storage format of each data item, constraints on data
Insulation between programs and data: Called program-data independence.
Allows changing data storage structures without having to change the DBMS access programs.
Data Abstraction: A data model is used to hide storage details and present
the users with a conceptual view of the database.
Abstract operation(OODB)
Support of multiple views of the data: Each user may see a different view of the
database, which describes only the data of interest to that user.
subset or virtual data
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