郁闷,中断调试后还是执行了

今天遇见一个很烦的问题,                    
            SqlDatabase db = (SqlDatabase)DatabaseFactory.CreateDatabase();
            using (DbConnection conn = db.CreateConnection())
            {
                conn.Open();
                DbTransaction trann = conn.BeginTransaction();
               
                try
                {
                    //领取库存
                    Insert(db, trann);
                    //减少库存
                    reduceStock(db, trann);
                    trann.Commit();
                    //trann.Rollback();

                }
                catch(Exception ex)
                {
                    trann.Rollback();
                    throw new MyException("数据保存错误！");
                }
            }
我用DAAB实现一个事务,但我在reduceStock中断后,结果显示过程reduceStock还是执行了,并且事务成功执行了,调试了很久,也不知道原因,晕啊