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Network model


The network model is a database model conceived as a more flexible alternative to the hierarchical model. Where the hierarchical model structures data as a tree of records, with each record having one parent record and many children, the network model allows each record to have multiple parent and child records, forming a lattice structure.

The network model does improve on the hierarchical model, but it is complex to use and implement. The relational model improves on the network model by separating the logical design of the database from the physical design. Both the network and hierarchical models mandate a fixed relationship between child and parent records, maintained internally by the database system. The relational model allows access to data via data relationship rather than the access paths or pointers provided by the hierarchical and network models.

History

In 1971, the Conference on Data Systems Languages (CODASYL) established a formal definition of the network database model.

See also

Navigational Database

01-04-2007 01:16:19
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