login_id not in table

            str = "select count(*) as cnt from staff_login where login_id = 'hafees' and password = encrypt('hafees')";

            com = new OracleCommand(str);
            orada = new OracleDataAdapter(com.CommandText, conn);
            dt = new DataTable();
            orada.Fill(dt);
            RowCount = dt.Rows.Count;
            for (int i = 0; i < RowCount; i++)
            {
                UserName = dt.Rows[i]["login_id"].ToString();
                Password = dt.Rows[i]["password"].ToString();
                if (UserName == txtUserName.Text && Password == txtPwd.Text)
                {

                    Response.Redirect("Welcome.aspx");
                }
                else
                {
                    lblMsg.Text = "Password wrong! Please try again!";
                }
            }

        }

Hi, I still new at ASP.NET and Oracle. I try to connect Oracle DB using apps that I make.. But once I click login it's popup and error which is "Column 'login_id' does not belong to table ." Can anyone help me on this? Struggle a week to solve this..