Question

我正在使用C＃和MYSQL，并且Rollback无法正常工作。我有三个删除语句，其中表第三个删除SQL不存在，在catch我正在做回滚，但它只发生在第三次

         string id = dataGridView1.Rows[index].Cells[0].Value.ToString();
         string strDelete = "DELETE FROM user WHERE id = " + id;
         OdbcTransaction transaction = null;
         OdbcCommand cmd = new OdbcCommand();
         cmd.Connection = Singleton.Instance.GetConnection();
         transaction = Singleton.Instance.GetConnection().BeginTransaction();
         cmd.Transaction = transaction;
         try
         {
             cmd.CommandText = strDelete;
             cmd.ExecuteNonQuery();
             // delete from userdata
             strDelete = "DELETE FROM userdata WHERE id = " + id;
             cmd.CommandText = strDelete;
             cmd.ExecuteNonQuery();
             // delete from usersystem
             strDelete = "DELETE FROM usersystem WHERE id = " + id;
             cmd.CommandText = strDelete;
             cmd.ExecuteNonQuery();
             // delete from user systemstatus. here table don't exists, will throw 
             // exception 
             strDelete = "DELETE FROM usersystemstatusAAAA WHERE id = " + id;
             cmd.CommandText = strDelete;
             cmd.ExecuteNonQuery();
             transaction.Commit();
         }
         catch (Exception ex)
         {
             // Attempt to roll back the transaction.
             try
             {
                 transaction.Rollback();
             }
             catch (Exception ex2)
             {
                 Console.WriteLine("  Message: {0}", ex2.Message);
             }

         }

这里提交前两个SQL语句，同时假设要回滚所有。

Answer 1

您需要检查MySQL数据库的存储类型。并非所有存储都是事务性的。例如，InnoDB有交易而MyISAM没有交易。

MyISAM与InnoDB MyISAM versus InnoDB

Answer 2

我怀疑你有第二个连接，并且连接/事务/命令存在混淆;尝试在您实际使用的连接上启动事务：

cmd.Connection = Singleton.Instance.GetConnection();
transaction = cmd.Connection.BeginTransaction();

另外，您可能希望在此处查看using块。

回滚在C＃中不起作用

2 个答案: