Explain the difference between a distributed database and distributed processing.

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  •  In distributed processing, a database’s logical processing is shared among two or more physically independent sites that are connected through a network. For example, the data input/output (I/O), data selection, and data validation might be performed on one computer, and a report based on that data might be created on another computer.
  • A distributed database, on the other hand, stores a logically related database over two or more physically independent sites. The sites are connected via a computer network. In contrast, the distributed processing system uses only a single-site database but shares the processing chores among several sites. In a distributed database system, a database is composed of several parts known as database fragments. The database fragments are located at different sites and can be replicated among various sites. Each database fragment is, in turn, managed by its local database process.
  •  Distributed processing does not require a distributed database, but a distributed database requires distributed processing (each database fragment is managed by its own local database process).
  • Distributed processing may be based on a single database located on a single computer. For the management of distributed data to occur, copies or parts of the database processing functions must be distributed to all data storage sites.
  • Both distributed processing and distributed databases require a network to connect all components.


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