public partial class Log
{
        public int LogID { get; set; }
        public int ActionID { get; set; }
        public DateTime InsertDate { get; set; }
}

public partial class LogInfo : Log
{
        public string ActionName { get; set; }
}

var qry = "select a.*, b.ActionName From Logs a join LogActions b on etc.."
var list = db.Database.SqlQuery<LogInfo>(qry).ToList();

public partial class LogInfo
{
        public Log Log { get; set; }
        public string ActionName { get; set; }
}

var list = from a in db.Logs
                         join b in db.LogActions on a.ActionID equals b.ActionID
                         select new LogInfo()
                         {
                             Log = a,
                             ActionName = b.Name
                         };