Return some query columns using LINQ

Question

I have a query that returns me all the columns and I’m using only two columns (id and nome) in my select2, I thought to bring only these columns, I wonder if it is possible to bring in the query only two columns Fornecedor.

I got the following:

Ifornecedorrepository

Task<IEnumerable<Fornecedor>> ObterParaAutocomplete(string text);

Vendordorrepository

public async Task<IEnumerable<Fornecedor>> ObterParaAutocomplete(string text)
{
    return await Db.Fornecedores.AsNoTracking()
        .Where(x => x.Nome.Contains(text))
        .OrderBy(p => p.Nome)
        .ToListAsync();
}

Suppliers

[HttpGet]
public async Task<IActionResult> ObterFornecedor(string text)
{

    if (string.IsNullOrEmpty(text))
    {
        return Json(new
        {
            result = ""
        });
    }
    else
    {
        var dados = _mapper
            .Map<IEnumerable<FornecedorViewModel>>(
                await _fornecedorRepository.ObterParaAutocomplete(text)
            );
        return Json(new
        {
            result = dados
        });
    }

}

Json result

Answer 1

One can create a ViewModel with two fields (in your field id and nome) and when using ORM Entity Framework do the following:

public class ViewModel 
{
    public int Id { get; set; }
    public string Nome { get; set; }
}

and then in your Interface IFornecedorRepository create a method:

Task<IEnumerable<ViewModel>> ObterParaAutocomplete(string text);

and implement it in the class FornecedorRepository:

public async Task<IEnumerable<ViewModel>> ObterParaAutocomplete(string text)
{
    return await Db.Fornecedores
        .AsNoTracking()
        .Where(x => x.Nome.Contains(text))
        .OrderBy(p => p.Nome)
        .Select(c => new ViewModel { Id = c.Id, Nome = c.Nome })
        .ToListAsync();
}

and this is very good for performance by the amount of information that is really needed.