SqlException (0x80131904): Invalid object name 'dbo.Categories'

Question

I am getting the exception above when I run an application. The application is using asp.net mvc 3 / C#. I made an mdf file and added it under App_Data folder in Visual Web Developer Express. I added connection strings to the web.config folder but when I run and browse to /store, I get the error above with the line var categories = storeDB.Categories.ToList(); highlighted. My database contains 6 tables and one of them is Category.

Controller:

EventCalendarEntities storeDB = new EventCalendarEntities();

public ActionResult Index()  
{  
    var categories = storeDB.Category.ToList();  
    return View(categories);  
}    

Connection strings in web.config file:

<connectionStrings>
   <add name="EventCalendarEntities"
        connectionString="data source=.\SQLEXPRESS;
        Integrated Security=SSPI;
        AttachDBFilename=|DataDirectory|\MvcEventCalendar.mdf;
        User Instance=true"
        providerName="System.Data.SqlClient" />
</connectionStrings>

Answer 1

This usually means a simple configuration issue:

• perhaps there genuinely is no such table
• perhaps the table is there, but there is no dbo scheme (it might be in Fred.Categories)
• perhaps the db is case-sensitive (which is fine), and the table is actually dbo.CATEGORIES

Any of these will cause the above exception. In particular, you state:

My database contains 6 tables and one of them is Category.

Now to a machine, Category != Categories

Answer 2

Try using model builder class.It is the way to configure or explicitly define the mapping between table and model class.

In your entity/context class try adding this code

protected override void OnModelCreating(DbModelBuilder modelBuilder)
    {
       base.OnModelCreating(modelBuilder);
       modelBuilder.Entity<Category>().ToTable("Category");
    }

Its a method.Make sure ur using all the including statements.