Hi Gevorg

I think in V8 you can access the database to run custom queries against a custom table via using a Scope...

github.com/umbraco/Umbraco-CMS/blob/853087a75044b814df458457dc9a1f778cc89749/src/Umbraco.Core/Scoping/IScope.cs

There is a ScopeProvider that has the job of creating a 'scope' object from which you can access the IUmbracoDatabase or run your SQL...

You can 'inject' the ScopeProvider into your custom controller...

So something like this:

    using System.Linq;
    using System.Web.Mvc;
    using Umbraco.Core.Persistence;
    using Umbraco.Core.Scoping;
    using Umbraco.Web.Mvc;

    namespace YourSiteNamespace.Controllers
    {
        public class CountriesController : SurfaceController
        {
            private readonly IScopeProvider scopeProvider;

            public CountriesController(IScopeProvider scopeProvider)
            {
                this.scopeProvider = scopeProvider;
            }
            // GET: Countries
            public ActionResult GetCountries()
            {
                using (var scope = scopeProvider.CreateScope(autoComplete: true))
                {
                    var sql = scope.SqlContext.Sql()
                        .Select("*")
                        .Where<MyCountryTable>(f=>f.IsCountry).OrderBy<MyCountryTable>(f=>f.CountryName);

                    var countries = scope.Database.Query<MyCountryTable>(sql);
                }
 var vm = new CountriesListViewModel();
vm.Countries = countries;
                return View("CountriesListPartial", vm);
            }
        }
}

or similar...

regards

Marc