Named groups of data models.

Object-Based Logical models

Record-Based Logical models

Physical models. (Binary, Infologycal, Sementic, Functional data Model)

3) What is the entity?

Entity is a distinguishable object that exists. Each entity is associated with the set of attributes describing it. For example, if we have the account as entity, that the number of accounts and account balance are attributes.

4) What is entity class?

Entity class is a collection of entities, is describes by the structure or formed of each of the entity of that class. An instants of an entity and is described by the values of attributes of the entity. In one entity class there are many entity instants.

5) Describe Network Model.

In this model data are represented by collections of records. Relationships among data are represented by links. Organization is that of arbitrary graph.



  1. Free Word-Groups Versus Phraseological Units Versus Words
  2. Lexico-Grammatical groups
  3. Political groups and parties

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