Network model and their Advantages and Disadvantages | Data models

NETWORK MODEL

INTRODUCTION-

The network model is a database model conceived as a flexible way of representing objects and their relationships. Its distinguishing feature is that the schema, viewed as a graph in which object types are nodes and relationship types are arcs, is not restricted to being a hierarchy or lattice.

The network model replaces the hierarchical model with a graph thus allowing more general connections among the nodes.The main difference of the network model from the hierarchical model is its ability to handle many to many relationships.In other words it allow a record to have more than one parent.

EXAMPLE-

ADVANTAGES OF NETWORK MODEL-

The major advantage of network model are-

1.) Conceptual simplicity-Just like the hierarchical model,the network model is also conceptually simple and easy to design.

2.) Capability to handle more relationship types-The network model can handle the one to many and many to many relationships which is real help in modeling the real life situations.

3.) Ease of data access-The data access is easier and flexible than the hierarchical model.

4.) Data integrity- The network model does not allow a member to exist without an owner.

5.) Data independence- The network model is better than the hierarchical model in isolating the programs from the complex physical storage details.

6.) Database standards

DIS-ADVANTAGE OF NETWORK MODEL-

1.) System complexity- All the records are maintained using pointers and hence the whole database structure becomes very complex.

2.) Operational Anomalies- The insertion,deletion and updating operations of any record require large number of pointers adjustments.

3.) Absence of structural independence-structural changes to the database is very difficult.

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Network model and its Advantages | data models

NETWORK MODEL

INTRODUCTION-

The network model is a database model conceived as a flexible way of representing objects and their relationships. Its distinguishing feature is that the schema, viewed as a graph in which object types are nodes and relationship types are arcs, is not restricted to being a hierarchy or lattice.

                The network model replaces the hierarchical model with a graph thus allowing more general connections among the nodes.The main difference of the network model from the hierarchical model is its ability to handle many to many relationships.In other words it allow a record to have more than one parent.

EXAMPLE-

ADVANTAGES OF NETWORK MODEL-

The major advantage of network model are-

1.) Conceptual simplicity-Just like the hierarchical model,the network model is also conceptually simple and easy to design.

2.) Capability to handle more relationship types-The network model can handle the one to many and many to many relationships which is real help in modeling the real life situations.

3.) Ease of data access-The data access is easier and flexible than the hierarchical model.

4.) Data integrity- The network model does not allow a member to exist without an owner.

5.) Data independence- The network model is better than the hierarchical model in isolating the programs from the complex physical storage details.

6.) Database standards

DIS-ADVANTAGE OF NETWORK MODEL-

1.) System complexity- All the records are maintained using pointers and hence the whole database structure becomes very complex.

2.) Operational Anomalies- The insertion,deletion and updating operations of any record require large number of pointers adjustments.

3.) Absence of structural independence-structural changes to the database is very difficult.

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Data models and their types | database managenent system

DATA MODELS

INTRODUCTION:-
It can be  defined as an integrated collection of concepts for describing and manipulating data,relationship between data and the constrains of the data in any organization.

It consists of three components:-

1.)Structured part:- It consist of set of rules according to which database can be connected.

2.) Manipulative part:- It defines the types of operations that are allowed on data.

3.) Set of integrity rules:-It ensures that the data is accurate.

PURPOSE OF DATA MODEL:- Purpose of data model is to represent the data and to make it understandable.

TYPES OF DATA MODEL:-

There are 3 types of data models:-

1.) Object based data models

2.) Physical data models

3.) Record based

1.) OBJECT BASED DATA MODELS:-It uses the concepts such as entities,attributes and relationship.It is of further 4 types:-

1.) ER(entity relationship)model

2.) Object oriented ER model

3.) Semantic model

4.) Functional model

2.) PHYSICAL DATA MODEL:-It describes how the data is stored in the computer representing the information such as record structure ,record modeling and access paths.

3.) RECORD BASED DATA MODEL:- These are used in describing the data at logical and view levels.These are used to specify the overall logical structure of the database.Record database models are of 3 types which are:-

1.) Hierarchical model

2.) Network model

3.) Relational model

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