Debug Lazy loading

Question

Sirs,

I would like to view all queries that are generated when I use Lazy loading. When debugging view only the main.

In the Training controller this way:

public class TreinamentosController : Controller
{
    private DbContext db = new DbContext();
    public ActionResult Index()
    {
        db.Configuration.LazyLoadingEnabled = true;
        IList<Treinamento> treinamentos = b.Treinamentos.ToList<Treinamento>();
        //var treinamentos = db.Treinamentos.Include(t =>t.Departamentos);
        return View(treinamentos.ToList());
    }

The view is like this:

<table class="table">
    <tr>
        <th>@Html.DisplayNameFor(model => model.Departamentos.NomeDepartamento)</th>
        <th>@Html.DisplayNameFor(model => model.NomeTreinamento)</th>
        <th>@Html.DisplayNameFor(model => model.Creditos)</th>
        <th></th>
    </tr>

    @foreach(var item in Model)
    {
        <tr>
            <td>@Html.DisplayFor(modelItem => item.Departamentos.NomeDepartamento)</td>
            <td>@Html.DisplayFor(modelItem => item.NomeTreinamento)</td>
            <td>@Html.DisplayFor(modelItem => item.Creditos)</td>
            <td>
                @Html.ActionLink("Editar", "Editar", new { id = item.TreinamentoID}) |
                @Html.ActionLink("Detalhes", "Detalhes", new { id = item.TreinamentoID }) |
                @Html.ActionLink("Excluir", "Excluir", new { id = item.TreinamentoID }) 
            </td>

        </tr>
    }
</table>

When debugging I see only the query related to the Training, I can’t see the query related to the department, as I see?

in debug:

{SELECT 
    [Extent1].[TreinamentoID] AS [TreinamentoID], 
    [Extent1].[DepartamentoID] AS [DepartamentoID], 
    [Extent1].[NomeTreinamento] AS [NomeTreinamento], 
    [Extent1].[Creditos] AS [Creditos]
    FROM [dbo].[Treinamento] AS [Extent1]}

Answer 1

This answer explains very well what it is Lazy Loading and how it works in Entity Framework, but in short:

In this case, Departamento is not loaded when a Training is loaded. When searching for Training data, what is filled in in Department are Dynamicproxy classes. These entities will only become objects of the respective Models when they are directly accessed.
-@Gypsy

So when one Departamento is at last loaded?

The moment you call him, but specifically in this part:

 <td>@Html.DisplayFor(modelItem => item.Departamentos.NomeDepartamento)</td>

At this time the Entity Framework does a search in your database and brings back the expected Department. The query he does is this (I just summarized the fields):

exec sp_executesql N'SELECT 
    [Extent1].[DepartamentoId] AS [DepartamentoId], 
    [Extent1].[Nome] AS [Nome]
    FROM [dbo].[Departamentoes] AS [Extent1]
    WHERE [Extent1].[DepartamentoId] = @EntityKeyValue1',N'@EntityKeyValue1 uniqueidentifier',@EntityKeyValue1='A96D7FCE-6FFE-4F97-B6DD-9A83DD8B0109'

Prior to this moment, he only makes a consultation of Treinamentos normal, that way:

 exec sp_executesql N'SELECT TOP (2) 
    [Extent1].[TreinamentoId] AS [TreinamentoId], 
    [Extent1].[Nome] AS [Nome], 
    [Extent1].[DepartamentoId] AS [DepartamentoId]
    FROM [dbo].[Treinamentoes] AS [Extent1]
    WHERE [Extent1].[TreinamentoId] = @p0',N'@p0 uniqueidentifier',@p0='72A8B3DC-A998-47D8-BCF6-D8CDF21DBD29'

The queries were generated by Entity Framework on the basic Details screen generated by Scaffolding from Visual Studio 2013.