Viva of Data Model.

🍂What is data model ?

A collection of conceptual tools to use for describe data .

Categories of Data Model

*Conceptual data model

Conceptual data models use concept such as entities,attributes and relationship.

*Record based data model 

Record based data represent data as by using the record structure. This model provide the concept that may be understand by end user.

The various categories of Record based data models are:

Hierarchical Data base

Hierarchical data model represent data as a hierarchical tree structure.

Network data model

Network data model represent  data as record type. The network model use the network or plex structure as its basic  data structure. 

Relational Data Model

Relational  Data Model  is based on  the concept of a relation, which is physically represented as a table.

*Object based data model 

A object  oriented  data model is a logic organisation of the real world object constraints on them and the relationship among object. 

* Physical data model 

Physical data model describe the data in terms of collection  of files,indices and other storage structure such as record formats,record ordering and access paths.

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