插入到C＃应用程序失败的Access数据库中

Question

我已经加入了两个表值并将这些值插入到另一个表中，但插入不起作用。我使用的是Access数据库，我使用下面的代码：

string query = "select t2.date,t1.FlightNo,t1.Dept_Time,t1.Arr_Time,t1.Route,t1.[Destination 1],t1.[Destination 2],t1.[Destination 3],t1.[Destination 4] From [FlightNumber]as t1 inner join [schedule]as t2 on t1.FlightNo=t2.FlightNo"; 

OleDbCommand cmd = new OleDbCommand(query, con); 

OleDbDataAdapter adp = new OleDbDataAdapter(cmd); 
dt1 = new DataTable(); 
adp.Fill(dt1); 
con.Open(); 
string query2 = "Insert into Monday (date,[Flight_no],[Dept_time],[Arr_time],Route,[dest_1],dest2,dest3,dest4)values(@date,@flight,@dept,@arr,@route,@dest1,@dest2,@dest3,@dest4)"; 
for (int i = 0; i < dt1.Rows.Count; i++) 
{ 
    OleDbCommand cmd1 = new OleDbCommand(query2, con); 

    cmd.Parameters.AddWithValue("@date", SqlDbType.NVarChar).Value = dt1.Rows[i]["date"].ToString(); 
    cmd.Parameters.AddWithValue("@flight", dt1.Rows[i]["FlightNo"]); 
    cmd.Parameters.AddWithValue("@dept", dt1.Rows[i]["Dept_Time"]); 
    cmd.Parameters.AddWithValue("@arr", dt1.Rows[i]["Arr_Time"]); 
    cmd.Parameters.AddWithValue("@route", dt1.Rows[i]["Route"]); 
    cmd.Parameters.AddWithValue("@dest1", dt1.Rows[i]["Destination 1"]); 
    cmd.Parameters.AddWithValue("@dest2", dt1.Rows[i]["Destination 2"]); 
    cmd.Parameters.AddWithValue("@dest3", dt1.Rows[i]["Destination 3"]); 
    cmd.Parameters.AddWithValue("@dest4", dt1.Rows[i]["Destination 4"]); 

    cmd1.ExecuteNonQuery(); 
    con.Close(); 
    MessageBox.Show("successfully inserted");    
} 

Answer 1

DATE是访问SQL一个reserved word，所以你需要用该列名在方括号中的INSERT命令（像你这样用[Flight_no]，[Dept_time]等）。

string query2 = "Insert into Monday ([date], ... 

Answer 2

除了什么戈德提及保留字日期，你可能会在性能更好，如果你不保持重建的命令和参数，特别是如果你有很多你想插入记录。相反，这样做......

string query2 = "Insert into Monday (date,[Flight_no],[Dept_time],[Arr_time],Route,[dest_1],dest2,dest3,dest4)values(@date,@flight,@dept,@arr,@route,@dest1,@dest2,@dest3,@dest4)"; 

//预构建的命令和参数ONCE
OleDbCommand的CMD1 =新的OleDbCommand（QUERY2，CON）;

cmd.Parameters.AddWithValue（“@ date”，dt1.Rows [i] [“date”]。ToString（））; cmd.Parameters.AddWithValue（“@ flight”，dt1.Rows [i] [“FlightNo”]）; cmd.Parameters.AddWithValue（“@ dept”，dt1.Rows [i] [“Dept_Time”]）; cmd.Parameters.AddWithValue（“@ arr”，dt1.Rows [i] [“Arr_Time”]）; cmd.Parameters.AddWithValue（“@ route”，dt1.Rows [i] [“Route”]）; cmd.Parameters.AddWithValue（“@ dest1”，dt1.Rows [i] [“Destination 1”]）; cmd.Parameters.AddWithValue（“@ dest2”，dt1.Rows [i] [“Destination 2”]）; cmd.Parameters.AddWithValue（“@ dest3”，dt1.Rows [i] [“Destination 3”]）; cmd.Parameters.AddWithValue（“@ dest4”，dt1.Rows [i] [“Destination 4”]）;

for (int i = 0; i < dt1.Rows.Count; i++) 
{ 
    cmd.Parameters[0].Value = dt1.Rows[i]["date"].ToString(); 
    cmd.Parameters[1].Value = dt1.Rows[i]["FlightNo"]); 
    cmd.Parameters[2].Value = dt1.Rows[i]["Dept_Time"]); 
    cmd.Parameters[3].Value = dt1.Rows[i]["Arr_Time"]); 
    cmd.Parameters[4].Value = dt1.Rows[i]["Route"]); 
    cmd.Parameters[5].Value = dt1.Rows[i]["Destination 1"]); 
    cmd.Parameters[6].Value = dt1.Rows[i]["Destination 2"]); 
    cmd.Parameters[7].Value = dt1.Rows[i]["Destination 3"]); 
    cmd.Parameters[8].Value = dt1.Rows[i]["Destination 4"]); 

    cmd1.ExecuteNonQuery(); 
} 

con.Close(); 
MessageBox.Show("successfully inserted");