Distributed Data Base Management System
Since the capability of networking, micro computing, & data base management system technologies evolve, distributed data base management are becoming an actuality. This is significant to distinguish among a networking system providing remote data base access and distributed data base access. This enables user to operate on data at one or more remote sites simultaneously and to ensure that work is carry out by following procedures that facilitates utilization of this data. In a true distributed database system user is not aware that the data is distributed. The following seven features explained the advantage of distributed data base system proposed by Stonebraker (1989):
- Transparency in Locating Data:
Query might be submitted to access distributed data without knowing the position of data.
- Transparency in Performance Measurement:
Query might be submitted from any node running with comparable performance
Supporting optional existence of multiple copies of data base objects.
- Transparency in Transaction:
Supports arbitrary transaction that updates the data at a number of sites.
- Transparency in Fragmentation:
Permits user to segment a relation into multiple pieces & place them at multiple sites according to particular distribution criteria.
- Scheme Change Transparency:
Enables to make the alteration only once when deleting or adding a data base object from a distributed database.
- Local Database Management Transparency:
Provides services without regard for the local data base system.