Linq not seeing properties - sql

Question

I have the following class and I'm trying to access it's properties from a different related class as follows:
var nuInfo = recipe.RECIPE_INGREDIENT
.Select(i => i.INGREDIENT.INGREDIENT_NUTRITIONAL_INFO)
.Where(ni => ni.NUTRITIONAL_INFO.Main == 1);
However, I can't access any (virtual or not) properties of INGREDIENT_NUTRITIONAL_INFO.
The INGREDIENT_NUTRITIONAL_INFO class is as follows:
public class INGREDIENT_NUTRITIONAL_INFO
{
public int IngredientId { get; set; }
public int Nutritional_InfoId { get; set; }
public double Amount { get; set; }
public DateTime DateSubmitted { get; set; }
public DateTime DateModified { get; set; }
public string SubmittedBy { get; set; }
public string ModifiedBy { get; set; }
public virtual AspNetUsers AspNetUsers { get; set; }
public virtual AspNetUsers AspNetUsers1 { get; set; }
public virtual INGREDIENT INGREDIENT { get; set; }
public virtual NUTRITIONAL_INFO NUTRITIONAL_INFO { get; set; }
}
Error Code is as follows:
CS1061 'ICollection' does not contain a definition for 'NUTRITIONAL_INFO' and no extension method 'NUTRITIONAL_INFO' accepting a first argument of type 'ICollection' could be found (are you missing a using directive or an assembly reference?)
Am I missing something in Linq? Am I trying to traverse across too many relationships?

Answer 1

The error is because you're not adding .First() or .FirstOrDefault() on the end of your query:
var nuInfo = recipe.RECIPE_INGREDIENT.Select(i => i.INGREDIENT.INGREDIENT_NUTRITIONAL_INFO)
.Where(ni => ni.NUTRITIONAL_INFO.Main == 1)
Your code is trying to access NUTRITIONAL_INFO as a property of the collection, not as the property of a member in the collection.

Answer 2

The problem is that nuInfo is not just one INGREDIENT_NUTRITIONAL_INFO object, your LINQ query returns a result as a IEnumerable<T>.
If you want to get a single result you can use First(),FirstOrDeafult, Single() or SingleOrDefault to instead return a single result.
var nuInfo = recipe.RECIPE_INGREDIENT
.Select(i => i.INGREDIENT.INGREDIENT_NUTRITIONAL_INFO)
.FirstOrDefault(ni => ni.NUTRITIONAL_INFO.Main == 1);