Monday, May 9, 2011

Entity Framework 4.1 Problem

One of the great improvements of Entity Framework 4.1 is the introduction of conventions. Unfortunately due to some time constraints the EF team had to remove the support for customizable conventions. Still, there are some default conventions already available.

And it was one of these conventions that bit me in the foot last week. I created the following model:

public class PizzaIngredient
{
public int PizzaIngredientId { get; set; }
[Range(1,10)]
public int Price { get; set; }
[Required]
public string IngredientName { get; set; }
public string Description { get; set; }
}

and the following context:

public class PizzaPlanetMVCContext : DbContext
{
public DbSet<PizzaPlanet.MVC.Models.PizzaIngredient> PizzaIngredients { get; set; }
}

However when running the application, the following error message was returned:

Invalid object name 'dbo.PizzaIngredients’.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Data.SqlClient.SqlException: Invalid object name 'dbo.PizzaIngredients’.

The reason is that there is a default convention that defines the name of the table by pluralizing the name of the entity(PizzaIngredient –> PizzaIngredients). As I had created my database up front, my table was called PizzaIngredient which of course resulted in an invalid query.

How can you solve this?

The simplest way to solve this, is by removing this convention. Therefore open up the context class and add the following code block:

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Conventions.Remove<PluralizingTableNameConvention>();
}

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