Slow SQL LINQ C# Entity Framework problems

Question

I am using Entity Framework, I have a list of objects (data taken from the database) with data from Clients,

public virtual DbSet<clientes> clientes {get;set;}


public IEnumerable<clientes> FindAll()
{   db.Configuration.LazyLoadingEnabled = false;
    return db.clientes.ToList();
}

and then on my form, I have a Grid

grid.datasource = clientes.ToList();

I’m calling the list right in the 'On Load' form, I’m only with 3 record in the database (SQLSERVER) and it’s taking more than 10 seconds to open the form..

In the class mapped the PK is this way :

[Key]
public int pk_cliente {get;set;}

I was wondering if the PK mapping is wrong and it’s getting lost somewhere.

Answer 1

For his reply, the slowness problem comes from the lazy load, which is possibly made for a great result. It will get slow even.

The function below resembles a repository, which is a very wrong approach to use with Entity Framework, which already implements a repository. Either way, load anticipation (or simply, use JOIN for relational databases) can be done as follows:

public IEnumerable<modelos> FindBy(string valor)
{
       return db.modelos
                 .Include(m => m.Peca)
                 .Include(m => m.Produto)
                 .AsEnumerable();
}

valor is not used or used, but I have kept it as an example.

Answer 2

I was using the context to do all the research, so when I gave the command db.clientes.Tolist(), within my context class I have other models, so he would go one by one (creating the mapping), then I would create a query for each event, so don’t let Entity mount select for me, I’ll do it myself as follows :

    private Context db = new Context();
    private IQueryable query;   


 public IEnumerable<modelos> FindBy(string valor)
    {
           query = from m in db.modelos
                   join p in db.pecas on m.fk_Peca equals p.pk_Peca
                   join po in db.produtos on m.fk_Produto equals  po.pk_Produto
                   select new { m,p,po};

        return query as IEnumerable<modelos>;
    }

Switching to the Gridview :

gridViewDetalhes.DataSource = _Modelos.FindBy(edtCodigoModelo.Text).ToList();

It helped a lot in my case, however I am working on this project with a friend, using the same type of notbook and same version of visual stuido (Community 2015) and when he was opening the form, it didn’t take long.

I hope I’ve helped!