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ASP.net MVC : Create MVC 5 Application using EF6 with Code First and Existing Database

I have to create an application in MVC 5 using EF6. I have already created the schema for the database in SQL Server 2012 and now I want to query this in my app.
The workflow that seems fit is Code First with Existing Database and I have tried to follow below resources but they are a little confusing to me as I am a beginner.
Is there a way I can still use my DB schema in SQL server and go ahead with Code First approach using generated data models from DB.
http://www.asp.net/mvc/overview/getting-started/getting-started-with-ef-using-mvc/creating-an-entity-framework-data-model-for-an-asp-net-mvc-application
http://www.asp.net/mvc/overview/getting-started/introduction/getting-started

Yes you can reverse engineer code first from existing DB schema. Here you can find instructions how do do it. Since you already created your DB schema you can start from point 3. Reverse Engineer Model.
This process will create for you a DbContext, POCO classes for the tables you selected in the wizard and the mappings. You can use it to query your DB.
When your DB schema changes in the future you can either regenerate POCO classes again or simply edit them by hand (if column type changed simply change the property type, if new column was added add new property to your class). Most devs use reverse engineer code first from existing DB only as a starting point when they need to target existing legacy database. After initial creation all future changes in schema are reflected by manually editing the classes that were originally generated by the tool.

how to detect the new database when change database in asp.net mvc4

The problem that when i change the new database then application not detected the new database and retreive error
The model backing the 'DBContext' context has changed since the
database was created. Consider using Code First Migrations to update
the database (http://go.microsoft.com/fwlink/?LinkId=238269).
but i don't using Migrations so i don't update-database by Package Manager Console
How can i fix this problem?

Actually it does detect changes in your database. The database differs from the model. The error message.
This error is thrown when the hash stored in the migrations history table does not match a calculated hash. (Have a look at __MigrationHistory table, might be under system tables)
If you delete this table the check is essentially disabled. You can achieve something similar by adding Database.SetInitializer<YourContextType>(null) to the startup of your application. The latter disables database creation from within that application, so if you want to create the database by code, you would need to do this from a separate application (for example an console app). I prefer to go this way for web applications.
Secondly: if you change your database manually (change columns, add tables, etc.) you need to adjust your model. So for each DDL statement, change your code.
If you are not using code first, you could update your existing model in the designer.

I ran into this problem when I first started with code first and mvc. the answer below is absolutely correct but you should go to the ASP.net website and do some tutorials on code first migrations. you need a better understanding how update database and initialize and migrations work.

Entity Framework to update the Model to reflect the changes in database

I am working on web Application which is developed by other programmer.
I have added a new table in database. So, now I wanted to add a correspondingly Model class. For this purpose the developer have already added a temple to auto-generate the model classes.
I am new to .NET and Entity Framework. From the information I got from internet that I can update the Model by using "Run Custom Tool". But when I execute it, It doesn't add new model class for the new table.
If anybody can give me any pointers, about the required steps to perform this operation.
Any help is very much appreciated.

Well, It depends which EF technique you are using.
1. Code First
If you are using code first, add the new model classes into the model section. Then from Package Console, generate the changes set and update the DB
Model First
Simply create a Model inside the model explorer, create the fields corresponding to DB tables and define the mappings.
Database First
Simply drag-drop the table from Server-Explorer and save it.
These might be of some help
http://visualstudiogallery.msdn.microsoft.com/ee4fcff9-0c4c-4179-afd9-7a2fb90f5838
http://www.asp.net/web-forms/tutorials/getting-started-with-ef/the-entity-framework-and-aspnet-getting-started-part-1

Keep Database Content On Model Change

Using the code-first approach available in the new 4.1 RC.
Is there any way to persist the current data stored in a database when the mode changes? The database is created by the entity framework, and usually the database is dropped and recreated on model changes.
Obviously as soon as the model is changed it will not be possible to use the context object to connect to the database to retrieve the data, so what are the options?

Code first doesn't support database migration / evolution yet. If you want to do incremental DB development use model first (EDMX) with DbContext Generator T4 template and Entity designer database generation pack which is able to create diff. scripts from the model.

From Scott Gu:
Importantly, though, the auto-create
database option is just an option – it
is definitely not required. If you
point your connection-string at an
existing database then EF “code first”
will not try and create one
automatically. The auto-recreate
option also won’t be enabled unless
you explicitly want EF to do this – so
you don’t need to worry about it
dropping and recreating your database
unless you’ve explicitly indicated you
want it to do so.

Entity Framework: How to update database when modifying Model

In Entity Framework 4 there are the options "Update Model from Database" and "Generate Database from Model". But what I'm missing is an option like
Update Database from Model
which reflects the changes made in the model (e.g. adding a new Property or Navigation-Property) by modifying the database schema (e.g. adding a new column). without losing its content.
Does someone know a way to achieve this or is there a t4 template that can perform a schema update without dropping existing tables? (I'm using Visual Studio 2010, .Net 4.0 and SQL Server 2008)
Thanks

Best way that I've found so far is to update the database first, for example adding a column to a table and then update the model from the database. This works well for small changes.