How to use different Entity Framework DbContext in ASP.NET MVC application scope?

I am currently building a web application with first MVC 4 code script and Entity Framework.

In the main structure of my application, I have Dbcontext(BlogDB)

to manage some classes Blog

. It works great as it creates all the tables I need in the database. Then I created a zone to host the online store. My idea is to create a split class DbContext

( OnlineStoreDB

) to handle classes used only for the online store.

My problem after startup OnlineStoreDB

, entity framework not only created tables for OnlineStore

, BUT ALSO dropped old tables.

My questions:

• If you know a way to keep old tables?
• How to accurately manage multiple EF context classes in a single application?

Code:

public class BlogDB : DbContext
{
    public BlogDB ()
        : base("DBConnection")
    {
        Database.SetInitializer(new BlogInitializer());
    }

    public DbSet<Blog> Blogs { get; set; }
    public DbSet<Author> Authors { get; set; }
    public DbSet<Comment> Comments { get; set; }
}

public class OnlineStoreDB : DbContext
{
    public OnlineStoreDB() :
        base("DbConnection")
    {
        Database.SetInitializer(new OnlineStoreInitializer());
    }

    public DbSet<Order> Orders { get; set; }
    public DbSet<Product> Products { get; set; }
    public DbSet<User> Users { get; set; }
}