Entity Framework

Entity Framework :

1. Entity framework is an ORM framework.

2. ORM stands for  object relational mapping.

ORM(object Relational Mapping) :

It is framework automatically creates classes based on database tables and the vice versa is also true,that is ,it can also automatically generate necessary SQL to create database tables based on classes.

Version of Entity framework 6.1.3

Entity framework supports the following three approaches

1.SchemaFirstApproach

2. ModelFirstApproach

3.CodeFirstApproach

 In the model first Approach we first create the entity model that is we create

a.Entities

b.Relationships between entities

c.Inheritance hierarchies

How update An .edmx File Using Entity Framework Data Model In Visual Studio 2017 or ASP .NET Core Web API

Open the project solution in that expand model folder shown below screen.

1.right clicking on your EDMX file and selecting Open With -> ADO.NET Entity Data Model Designer 

2.Right click on the designer surface of the EDMX designer and click Update Model From Database...

All entities are refreshed by default, new entities are only added if you select them.

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