訪問如何運行查詢使用參數

Question

在使用中獲得此代碼更新日期時間的Fileds PARAMS

SQL = "update ConfTbl set D_from = @MyFrom , D_to = @MyTo where Code = " + Convert.ToInt32(TmpCode1) + ""; 
OleDbCommand Cmd = Conn.CreateCommand(); 
OleDbParameter dateparam1 = Cmd.Parameters.AddWithValue("@MyFrom", DbType.DateTime); 
dateparam1.Value = dt_From.Value; 
OleDbParameter dateparam2 = Cmd.Parameters.AddWithValue("@MyTo", DbType.DateTime); 
dateparam2.Value = dt_To.Value; 
Cmd.CommandText = SQL; 
Cmd.ExecuteNonQuery(); 

如何改變這種對運行查詢兩個日期之間找到？

財產以後這樣的：select * from ConfTbl where Tdate >= #MyFrom# and Tdate <= #MyTo#

我試試這個：

SQL = @"select * from ReturnConfTbl where Tdate >= @MyFrom and Tdate <= @MyTo"; 
     OleDbCommand Cmd = Conn.CreateCommand(); 
     OleDbParameter dateparam1 = Cmd.Parameters.AddWithValue("@MyFrom", DbType.DateTime); 
     dateparam1.Value = dt_from_A.Value; 
     OleDbParameter dateparam2 = Cmd.Parameters.AddWithValue("@MyTo", DbType.DateTime); 
     dateparam2.Value = dt_to_A.Value; 
     Cmd.CommandText = SQL; 
     Cmd.ExecuteNonQuery(); 
     adp = new OleDbDataAdapter(SQL, Conn); 
     adp.Fill(dsView, "ReturnConfTbl"); 
     adp.Dispose(); 
     this.dataGridView3.DataSource = dsView.Tables[0].DefaultView; 

，並得到這個錯誤：Data type mismatch in criteria expression。

Answer 1

您可以使用BETWEEN關鍵字。例如

SELECT * 
FROM ConfTbl 
WHERE 
    Tdate BETWEEN #MyFrom# AND #MyTo# 

Answer 2

只是看看聲明的TSQL .. http://msdn.microsoft.com/en-us/library/ms187922.aspx