Big Tables in Entity Framework

Question

I have an WEB SQL in Windows Azure Server, and I need search an item in a table with 40.000 rows. The execution time of the query is one minute, too long for a web app (or any kind of application..). What ai do for reduce this time?

My question is similar to this: Entity Framework Very Large Table to List , but the answer is no acceptable because the method of paging is large too.

Code with search:

    public ActionResult SearchNcm(string typeSearch, string searchString)
    {
        var ncms = repository.VIEWNCM.ToList();

        if (Request.IsAjaxRequest())
        {
            if (!String.IsNullOrEmpty(searchString))
            {
                switch (typeSearch)
                {
                    case "cod":
                        ncms = ncms.Where(e => e.CODIGO_LEITURA.ToLower().Contains(searchString.ToLower()) || e.CODIGO.ToLower().Contains(searchString.ToLower())).ToList();
                        break;
                    default:
                        ncms = ncms.Where(e => e.DESCRICAO.ToLower().Contains(searchString.ToLower())).ToList();
                        break;
                }
            }
        }



        return PartialView("BuscarNcm", ncms);
    }

Answer 1

Not an answer but I need the space to expand on my comment above:

Remember that IQueryable and IEnumerable won't do anything until you either iterate or call ToList(). That means you can do things like:

var ncms = repository.VIEWNCM; // this should be IQueryable or IEnumerable - no query yet

if(Request.IsAjaxRequest())
{
    if(!string.IsNullOrEmpty(searchString))
    {
        switch(typeSearch)
        {
                case "cod":
                    // No query here either!
                    ncms = ncms.Where(e => e.CODIGO_LEITURA.ToLower().Contains(searchString.ToLower()) || e.CODIGO.ToLower().Contains(searchString.ToLower()));
                    break;
                default:
                    // Nor here!
                    ncms = ncms.Where(e => e.DESCRICAO.ToLower().Contains(searchString.ToLower()));
                    break;
            }
        }
    }
}
// This is the important bit - what happens if the request is not an AJAX request?
else
{
    ncms = ncms.Take(1000); // eg, limit to first 1000 rows
}

return PartialView("BuscarNcm", ncms.ToList()); // finally here we execute the query before going to the View

You probably also need a default filter if the searchString is empty