what is difference between a Model and an Entity

Question

I am confused to understand what is the meaning of this words:

Entity, Model, DataModel, ViewModel

Can an

Answer 1

First of all,to know about Entity you must know about Class. All of them represent same fields but the terminology changes based on declaration.

Let us consider a table from any database[SQL,ORACLE,Informix,Cassandra..] as example.

CLASS:

Generally a table is a considered as a class until it is added to edmx or dbmx.

 //Student class
        public class Student()
        {
        //Properties
        public int StudentNumber;
        public string StudentName;
        }

ENTITY:

• After drag drop/adding the table into dbmx/edmx it is referred to as Entity.

• Each Entity is generated from its corresponding class and we can add attributes to entity which are used for performing operations using
  linq or entity.

DATAMODEL:

• Contains all the fields in table.

• DATAMODEL is a direct class reference to your cshtml or controller where you can access the attributes to perform CRUD operations.

VIEWMODEL:

• Some situations occur where we need to perform CRUD operations more than one model(table).
• So we combine all our required models in a class and define them in its constructor.

Example: Lets assume

//Student class
public class Student()
{
//Properties
public int StudentNumber;
public string StudentName;
}
//Marks Class
Public class Marks()
{
public int Maths;
public int Physics;
public int Chemistry;

//Now sometimes situations occur where we have to use one datamodel inside //other datamodel.
public Student StudentModel;
}