Distributed Database System
A distributed database system consists of a collection of sites, each of which maintains a local database system. Each site is able to process local transactions–those transactions that access data only at that single site. In addition, a site may participate in the execution of global transactions–those transactions that access data at several sites. The execution of global transactions requires communication among the sites.
The advantages of Distributed Database System
- The primary advantages of distributed database systems is the ability to share and access data in a reliable and efficient manner. A user at one site may be able to access data that is available at another site.
- It reflects organisational structure
- If distributed over several locations then improved availability of DBMS. A failure of a communication link making some sites inaccessible does not make the entire system inoperable.
- Speed of database access may be better than that achievable from a remote centralised database.
- It is much easier to expand. New sites can be added to the network without affecting the operations of other sites.