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Types of Database model - Computer science fundamentals tutorial

Database model & it's types in DBMS

 Database model: - Database model defines the logical design and structure of database and defines how data will be stored and updated in a database management. Data Models are fundamental entities to introduce abstraction in a DBMS.
Types of Database model: - 
There are four types database model in DBMS.  The models are 
1) Hierarchical Model
 2)  Network Model
 3) Entity relationship model (ER model)
4) Relational model
now we discuss about each models.
1) Hierarchical Model: - This database model organizes data into a tree like structure with a single root to which all the other data is linked. The hierarchy starts from root data and expands like tree, adding child nodes to the parent nodes. In this model a child node will only have a single parent node. This model efficiently describes many real world relationship like index of a book, recipes. In hierarchical model, data is organized into tree like structure with one, one to many relationship between two different types of data.


 2)  Network Model: - This is an extension of the hierarchical model. In this model data is organized more like a graph and are allowed to have more than one parent node. In this database model data is more related as more relationship established in this model. As the data is related, hence accessing the data is also easier and fast. This database model was used to map many to many data relationship.



 3) Entity relationship model (ER model): - In this model relationship are created by dividing objects of interest into entity and its characteristic into attributes. ER model are define to represent the relationship into pictorial form to make it easier for different situation to understand. This model is good to design a database which can be turn into tables in relational mode.


       4) Relational model: - In this model, data is organized into two dimensional tables and relationship is maintain by storing a common filed. Basic structure of data in the relational model is tables. All the information related to a particular type is stored in rows of that table.



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