public static List <PressureByDay> GetPressure()
        {
            ISession             session  = SessionManager.GetSession();
            List <PressureByDay> pressure = new List <PressureByDay>();


            if (session == null)
            {
                return(null);
            }

            var PressureData = session.Execute("select * from \"pressure_by_day\"");


            foreach (var hd in PressureData)
            {
                PressureByDay h = new PressureByDay();
                h.cityID = hd["city_id"] != null ? hd["city_id"].ToString() : string.Empty;
                h.date   = hd["date"] != null?DateTime.Parse(hd["date"].ToString()) : DateTime.Parse(string.Empty);

                h.eventTime = hd["event_time"] != null?DateTime.Parse(hd["event_time"].ToString()) : DateTime.Parse(string.Empty);

                h.pressure = hd["pressure"] != null ? hd["pressure"].ToString() : string.Empty;
                pressure.Add(h);
            }
            return(pressure);
        }
        public static PressureByDay GetPressureByEventTime(string city_id, string date, string eventTime)
        {
            ISession session = SessionManager.GetSession();

            PressureByDay p = new PressureByDay();

            if (session == null)
            {
                return(null);
            }

            Row PressureData = session.Execute("select * from \"pressure_by_day\" where \"city_id\"='" + city_id + "' and \"date\"='" + date + "' and \"event_time\"='" + eventTime + "'").FirstOrDefault();

            if (PressureData != null)
            {
                p.cityID = PressureData["city_id"] != null ? PressureData["city_id"].ToString() : string.Empty;
                p.date   = PressureData["date"] != null?DateTime.Parse(PressureData["date"].ToString()) : DateTime.Parse(string.Empty);

                p.eventTime = PressureData["event_time"] != null?DateTime.Parse(PressureData["event_time"].ToString()) : DateTime.Parse(string.Empty);

                p.pressure = PressureData["pressure"] != null ? PressureData["pressure"].ToString() : string.Empty;
            }

            return(p);
        }