为什么数据会自动清除?

public bool InsertInfo(string NOID, DataSet ds, string dyno, string ck, DateTime dt, string fx, string czy)
    {
        bool result = false;
        OleDbConnection Ocon = new OleDbConnection(connection);
        Ocon.Open();
        using (OleDbTransaction Otran = Ocon.BeginTransaction())
        {
            using (OleDbCommand Ocmd = Ocon.CreateCommand())
            {
                Ocmd.Transaction = Otran;
                try
                {
                    for (int i = 0; i < ds.Tables["Info"].Rows.Count; i++)
                    {
                        int tm_xh = i + 1;
                        string tm = ds.Tables["Info"].Rows[i]["tm"].ToString();
                        decimal lrsl = Convert.ToDecimal(ds.Tables["Info"].Rows[i]["sl"].ToString());
                        string zdr = "扫描枪";
                        string cw = "cw";
                        string wlbm = ds.Tables["Info"].Rows[i]["wlbm"].ToString();
                        string xp = ds.Tables["Info"].Rows[i]["xp"].ToString();
                        Ocmd.CommandText = @"insert into tm (""TM_NO"",""TM_XH"",""TM"",""CK"",""DYNO"",""LRSL"",""ZDR"",""ZDRQ"",""SFKD"",""CW"",""WLBM"",""XP"",""FX"",""CZY"") values ('" + NOID + "'," + tm_xh + ",'" + tm + "','" + ck + "','" + dyno + "'," + lrsl + ",'" + zdr + "',sysdate,'N','" + cw + "','" + wlbm + "','" + xp + "'," + fx + ",'" + czy + "')";
                        Ocmd.ExecuteNonQuery();
                    }
                    Otran.Commit();
                    result = true;
                }
                catch (Exception ex)
                {
                    Otran.Rollback();
                    throw ex;
                }
                finally
                {
                    if (Ocon.State != ConnectionState.Closed)
                        Ocon.Close();
                    Ocon.Dispose();
                }
            }        }
        return result;
    }

在提交数据时网络断开了,然后提示提交失败 ,但表中的数据也自动清除了,为什么? --------------------编程问答-------------------- Rollback，回滚

补充：.NET技术 ,  C#