C＃MySql TransactionScope

Question

我的系統在同一個MySql中有2個數據庫。業務是確保數據在同一事務中完全插入到2個數據庫中。下面是我的示例：

public void test() 
{ 
    int returnValue = 0; 
    System.IO.StringWriter writer = new System.IO.StringWriter(); 
    try 
    { 
     using (TransactionScope scope = new TransactionScope()) 
     { 
      returnValue = TestA(returnValue, writer); 

      returnValue = TestB(returnValue, writer); 

      scope.Complete(); 
     } 
    } 
    catch (Exception ex) 
    { 
    } 
} 

private static int TestB(int returnValue, System.IO.StringWriter writer) 
{ 
    using (MySqlConnection connection2 = new MySqlConnection("server=localhost;database=test;user id=root;password=root;port=3307;characterset=utf8;connectiontimeout=72000;")) 
    { 
     connection2.Open(); 

     // Execute the second command in the second database. 
     returnValue = 0; 
     MySqlCommand command2 = new MySqlCommand("Insert tbb (`time`)value ('10:00:00')", connection2); 
     returnValue = command2.ExecuteNonQuery(); 
     writer.WriteLine("Rows to be affected by command2: {0}", returnValue); 
    } 
    return returnValue; 
} 

private static int TestA(int returnValue, System.IO.StringWriter writer) 
{ 
    using (MySqlConnection connection1 = new MySqlConnection("server=localhost;database=test1;user id=root;password=root;port=3307;characterset=utf8;connectiontimeout=72000;")) 
    { 
     connection1.Open(); 

     // Create the SqlCommand object and execute the first command. 
     MySqlCommand command1 = new MySqlCommand("Insert tb1 (`Name`, `Value`)value ('ai', '2017-04-26')", connection1); 
     returnValue = command1.ExecuteNonQuery(); 
     writer.WriteLine("Rows to be affected by command1: {0}", returnValue); 
    } 

    return returnValue; 
} 

當我跑，我得到了錯誤：

Multiple simultaneous connections or connections with different connection strings inside the same transaction are not currently supported.

它爲什麼會發生？

如果無法修復，請給我其他解決方案。

Answer 1

private static int TestA(int returnValue, System.IO.StringWriter writer) 
{ 
    .... USE SAME CONNECTION AS TESTA HERE 

    // Create the SqlCommand object and execute the first command. 
                 ****THIS***** 
    MySqlCommand command1 = new MySqlCommand("Insert `test1`.`tb1` (`Name`, `Value`)value ('ai', '2017-04-26')", connection1); 
                 ****THIS***** 
    returnValue = command1.ExecuteNonQuery(); 
    writer.WriteLine("Rows to be affected by command1: {0}", returnValue); 
} 

return returnValue; 

}

所以，我的意思是....不使用2個連接。使用1個連接，並與表toghether指定數據庫名稱

Answer 2

做這樣的：

MySqlConnection conn = new MySqlConnection(); 
     private int TestB(int returnValue, System.IO.StringWriter writer) 
     { 
      MySqlConnection conn = new MySqlConnection("server=localhost;database=test;user id=root;password=root;port=3307;characterset=utf8;connectiontimeout=72000;"); 

       conn.Open(); 

       // Execute the second command in the second database. 
       returnValue = 0; 
       MySqlCommand command2 = new MySqlCommand("Insert tbb (`time`)value ('10:00:00')", conn); 
       returnValue = command2.ExecuteNonQuery(); 
       writer.WriteLine("Rows to be affected by command2: {0}", returnValue); 
       conn.Close(); 
       return returnValue; 
     } 

     private int TestA(int returnValue, System.IO.StringWriter writer) 
     { 
      conn = new MySqlConnection("server=localhost;database=test1;user id=root;password=root;port=3307;characterset=utf8;connectiontimeout=72000;"); 

       conn.Open(); 

       // Create the SqlCommand object and execute the first command. 
       MySqlCommand command1 = new MySqlCommand("Insert tb1 (`Name`, `Value`)value ('ai', '2017-04-26')", conn); 
       returnValue = command1.ExecuteNonQuery(); 
       writer.WriteLine("Rows to be affected by command1: {0}", returnValue); 

       conn.Close(); 

      return returnValue; 
     } 

Answer 3

不能創建一個TransactionScope內的多個MySqlConnection對象;如果你這樣做，你會看到你看到的錯誤。這被追蹤爲MySQL Bug 50773。

您可能想升級到https://github.com/mysql-net/MySqlConnector（與MySql.Data兼容的OSS MySQL連接器庫），其中does support TransactionScope。