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 the data might be created on another computer.
Distributed database stores a logically related database over two or more physically independent sites. The sites are connected via a computer network. In a distributed database system, a database is composed of several parts known as database fragments.
From the two previous figures:
? 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.
Distributed database management systems (DDBMS)
Governs the storage and processing of logically related data over interconnected computer systems in which both data and processing functions are distributed among several sites.
Development history for DDBMS
During 1970s, corporations implemented centralized database management systems to meet their structured information needs. such information, generated by procedural programming languages.
المادة المعروضة اعلاه هي مدخل الى المحاضرة المرفوعة بواسطة استاذ(ة) المادة . وقد تبدو لك غير متكاملة . حيث يضع استاذ المادة في بعض الاحيان فقط الجزء الاول من المحاضرة من اجل الاطلاع على ما ستقوم بتحميله لاحقا . في نظام التعليم الالكتروني نوفر هذه الخدمة لكي نبقيك على اطلاع حول محتوى الملف الذي ستقوم بتحميله .
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