グリッドにバインドするには時間がかかる

Question

関数を使ってデータベースからデータを取得していますが、それをクラスに変換してグリッドに渡すには10秒かかります。ここで

は私のコードです：ここでは

NpgsqlDataAdapter adapt = new NpgsqlDataAdapter(@"SELECT m_time_stamp, m_event_log_description, m_wind_speed, m_rpm, m_power from logs.func_event_log(
    '"+id+ @"',                
    '" + myDateFrom + @" 00:00:00' , '" + myDateTo + @" 23:59:59.999'                                   
) 
t1 (m_time_stamp timestamp without time zone, m_event_log_description text, 
m_user_description varchar, m_event_type_description varchar, 
m_wind_speed real, m_rpm real, m_power real, 
m_event_type_id int, m_event_number varchar) ", cn); 

adapt.Fill(ds); 

EventEntryForAllTurbines evnt = new EventEntryForAllTurbines(); 

は、この遅延の主な原因である：

var data = (from t in ds.AsEnumerable() select new EventEntryForAllTurbines { 
    Timestamp = (DateTime)t["m_time_stamp"], 
    Description = (string)t["m_event_log_description"], 
    WindSpeed = (float)t["m_wind_speed"], 
    RPM = (float)t["m_rpm"], 
    Power = (float)t["m_power"] 
}); 

con.Close(); 
con.Dispose(); 
return new CustomJsonResult { Data = data }; 

Answer 1

string sql = "SELECT * FROM tbl_student WHERE studentname = @param"; 
NpgsqlCommand command = new NpgsqlCommand(sql,conn); 
command.Parameters.Add("@param", textBox_studentname.Text); //add the parameter into the sql command 

DataTable dt = new DataTable(); 
//load the DataReader object of the command to the DataTable 
dt.Load(NpgsqlDataReader reader = command.ExecuteReader(CommandBehavior.CloseConnection)); 
GridView1.DataSource = dt;