How to create a entity data model using database first approach.

Here we will learn how you can create a entity data model from an existing database (Known as database first approach). Please refer this to know what is a database first approach.

Create an Entity Data Model In a Separate project : 
Below are the steps to create a data model using database first approach (EF 4.5 VS 2012):

Step 1: Open Visual Studio 2012 > File > New Project > Windows Template > Class Library > Give it a name 'EntityFrameworkModel' > OK

Delete the default Class1.cs that gets created in the project. 

Step 2:Right click on the project in Solution Explorer > Add > New Item Select the Data Template > ADO.NET Entity Data Model and click Add.

In the Entity Data Model Wizard, choose 'Generate From Database' and click Next.

Create a new Data Connection or choose from an existing one. If you want to change the database connection then click on New Connection. A popup will open.

Select the Server name.You can either choose windows authentication or SQL server authentication.In SQL server authentication you need to provide the username and password. Then select the database name you want to connect and click on test connection. If it will show a successful message then click on OK button and proceed.

Step 3: Now choose the Database Objects you want to include in your Entity Data Model (EDM). Here I choose all the four tables 'Department' ,'Employee' ,'LogInDetails' and 'Salary'. As i dont have any stored procedure and view in my database so am not going to select any SP and view.If you want to change the name of the model you can change it under model namespace textbox. Click Finish to complete the wizard.

Then you will able to see the .edmx file as below.

You will find the connection string in the app.config file where you will find find the schema files (.csdl, .mls, .ssdl) :

Build the project in Release mode (Go to Build > Build EntityFrameworkModel) and make sure that there are no errors. A model defined by the Entity Data Model is now ready.

If you want to know how to use this entity data model in another .Net application to communicate with the database, then here you will find the link which will help you to achieve this.
 

Hope this is helpful. :)