我已经看过System.Transactions命名空间，并且想知道，我是否真的可以使用此命名空间使用RDMBS？
但是，当我看到一些示例时，我不明白System.Transactions如何完成简单尝试之外的工作并获得成功/失败的结果？
这是MSDN网站上的示例，我知道它可能非常简单，但是我无法理解此示例中的好处，有人可以告诉我以下示例中的简单try/catch和Transaction范围之间的区别是什么。
如果我应该制作一个RDBMS(创建自己的RDMBS)，我理解我们必须向执行操作的磁盘写入大量日志，最后在回滚的情况下撤消这些操作，但是这里没有任何内容关于撤消任何事情。
// This function takes arguments for 2 connection strings and commands to create a transaction
// involving two SQL Servers. It returns a value > 0 if the transaction is committed, 0 if the
// transaction is rolled back. To test this code, you can connect to two different databases
// on the same server by altering the connection string, or to another 3rd party RDBMS by
// altering the code in the connection2 code block.
static public int CreateTransactionScope(
string connectString1, string connectString2,
string commandText1, string commandText2)
{
// Initialize the return value to zero and create a StringWriter to display results.
int returnValue = 0;
System.IO.StringWriter writer = new System.IO.StringWriter();
try
{
// Create the TransactionScope to execute the commands, guaranteeing
// that both commands can commit or roll back as a single unit of work.
using (TransactionScope scope = new TransactionScope())
{
using (SqlConnection connection1 = new SqlConnection(connectString1))
{
// Opening the connection automatically enlists it in the
// TransactionScope as a lightweight transaction.
connection1.Open();
// Create the SqlCommand object and execute the first command.
SqlCommand command1 = new SqlCommand(commandText1, connection1);
returnValue = command1.ExecuteNonQuery();
writer.WriteLine("Rows to be affected by command1: {0}", returnValue);
// If you get here, this means that command1 succeeded. By nesting
// the using block for connection2 inside that of connection1, you
// conserve server and network resources as connection2 is opened
// only when there is a chance that the transaction can commit.
using (SqlConnection connection2 = new SqlConnection(connectString2))
{
// The transaction is escalated to a full distributed
// transaction when connection2 is opened.
connection2.Open();
// Execute the second command in the second database.
returnValue = 0;
SqlCommand command2 = new SqlCommand(commandText2, connection2);
returnValue = command2.ExecuteNonQuery();
writer.WriteLine("Rows to be affected by command2: {0}", returnValue);
}
}
// The Complete method commits the transaction. If an exception has been thrown,
// Complete is not called and the transaction is rolled back.
scope.Complete();
}
}
catch (TransactionAbortedException ex)
{
writer.WriteLine("TransactionAbortedException Message: {0}", ex.Message);
}
catch (ApplicationException ex)
{
writer.WriteLine("ApplicationException Message: {0}", ex.Message);
}
// Display messages.
Console.WriteLine(writer.ToString());
return returnValue;
}
在上面的示例中，我们要做什么？我想SQL Client库会正确执行所有操作吗？这是否意味着System.IO.StringWriter将包含所有成功文本或所有失败文本？还是TransactionScope范围之间有任何锁定？
最佳答案
首先，TransactionScope与try/catch不同。 TransactionScope是事务的名称范围。必须通过在范围上调用Complete来明确提交范围内的事务。任何其他情况(包括范围中引发的异常)都将导致使用using块完成处理，该块将处置范围并隐式回滚未完成的事务，但它将不处理该异常。
在基本方案中，来自System.Transactions的事务的行为与db客户端事务相同。 System.Transactions提供以下附加功能:
关于.net - System.Transactions的实际用途是什么？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/3537134/