What is data model [DBMS-5]

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Data Model

-Data model is used to describe of the structure of the database and to hide of the storage details and present the users with the conceptual view of the database.
-In other words how to store data in the database is known as data model.
-There are three types of data model:
                                                            hierarchical data model
                                                            network data model
                                                            relational data model

Hierarchical data model:

-hierarchical data model is nothing but a incurred tree like structure.
-It represents data and relationship between data item in the model of the involved tree.
-It is the most popular data model other system based on the this model.
-It is very simply to con street and operate on the simple language is used.
File:Hierarchical Model.svg - Wikimedia Commons

Network data model:

-It represents data in a network structure.
-In the network data model data are in link wise.
-It is able to model complex relationship and represent semantics of add or delete on a relationship.
-It is used for modifying by using record types and relationship types.
File:Network Model.svg - Wikimedia Commons

relational data model:

-To overcome the drawbacks of the hierarchical data model and network data model we used the relational data model.
-Relational data model is nothing but a table.
-In the table all coulombs are known as attributes.
-all the rows are known as tuples and tools.  
File:Relational Model.svg - Wikimedia Commons 

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