我想为我的数据库调用(使用C#和用于访问数据库的Microsoft技术)编写一些包装器代码，并在“ transient ”异常时自动重试。暂时的，我的意思是说，很有可能最终解决(相对于永远不会起作用的逻辑错误)。我能想到的例子包括:
我曾计划使用SqlException的错误号来发现这些错误。因此，例如:
List<RunStoredProcedureResultType> resultSet = null;
int limit = 3;
for (int i = 0; i < limit; ++i)
{
bool isLast = i == limit - 1;
try
{
using (var db = /* ... */)
{
resultSet = db.RunStoredProcedure(param1, param2).ToList();
}
//if it gets here it was successful
break;
}
catch (SqlException ex)
{
if (isLast)
{
//3 transient errors in a row. So just kill it
throw;
}
switch (ex.Number)
{
case 1205: //deadlock
case -2: //timeout (command timeout?)
case 11: //timeout (connection timeout?)
// do nothing - continue the loop
break;
default:
//a non-transient error. Just throw the exception on
throw;
}
}
Thread.Sleep(TimeSpan.FromSeconds(1)); //some kind of delay - might not use Sleep
}
return resultSet;
(对我来说，如果有任何错误，请原谅，我只是即时编写的。我也意识到我可以很好地将其包装起来...)
因此，关键问题是:我应该将哪些数字视为“ transient ”(我意识到我认为 transient 的数字可能与其他人认为 transient 的数字不同)。我在这里找到了一个不错的 list :
https://msdn.microsoft.com/en-us/library/cc645603.aspx
但是它的庞大和注释非常有用。 是否有其他人建立过类似的 list ？
更新
最后，如果错误是已知的“非暂时性错误”列表中的一个，则我们选择了“错误列表”，通常是程序员错误。我列出了我们用作答案的数字列表。
最佳答案
sql Azure中有一个[SqlDatabaseTransientErrorDetectionStrategy.cs]类，用于瞬时故障处理。它涵盖了几乎所有类型的可以视为 transient 的异常代码。这也是Retry strategy的完整实现。
在此处添加摘要以供将来引用:
/// <summary>
/// Error codes reported by the DBNETLIB module.
/// </summary>
private enum ProcessNetLibErrorCode
{
ZeroBytes = -3,
Timeout = -2,
/* Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding. */
Unknown = -1,
InsufficientMemory = 1,
AccessDenied = 2,
ConnectionBusy = 3,
ConnectionBroken = 4,
ConnectionLimit = 5,
ServerNotFound = 6,
NetworkNotFound = 7,
InsufficientResources = 8,
NetworkBusy = 9,
NetworkAccessDenied = 10,
GeneralError = 11,
IncorrectMode = 12,
NameNotFound = 13,
InvalidConnection = 14,
ReadWriteError = 15,
TooManyHandles = 16,
ServerError = 17,
SSLError = 18,
EncryptionError = 19,
EncryptionNotSupported = 20
}
进一步检查情况，以检查错误代码是否在sql异常中返回:
switch (err.Number)
{
// SQL Error Code: 40501
// The service is currently busy. Retry the request after 10 seconds. Code: (reason code to be decoded).
case ThrottlingCondition.ThrottlingErrorNumber:
// Decode the reason code from the error message to determine the grounds for throttling.
var condition = ThrottlingCondition.FromError(err);
// Attach the decoded values as additional attributes to the original SQL exception.
sqlException.Data[condition.ThrottlingMode.GetType().Name] =
condition.ThrottlingMode.ToString();
sqlException.Data[condition.GetType().Name] = condition;
return true;
// SQL Error Code: 10928
// Resource ID: %d. The %s limit for the database is %d and has been reached.
case 10928:
// SQL Error Code: 10929
// Resource ID: %d. The %s minimum guarantee is %d, maximum limit is %d and the current usage for the database is %d.
// However, the server is currently too busy to support requests greater than %d for this database.
case 10929:
// SQL Error Code: 10053
// A transport-level error has occurred when receiving results from the server.
// An established connection was aborted by the software in your host machine.
case 10053:
// SQL Error Code: 10054
// A transport-level error has occurred when sending the request to the server.
// (provider: TCP Provider, error: 0 - An existing connection was forcibly closed by the remote host.)
case 10054:
// SQL Error Code: 10060
// A network-related or instance-specific error occurred while establishing a connection to SQL Server.
// The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server
// is configured to allow remote connections. (provider: TCP Provider, error: 0 - A connection attempt failed
// because the connected party did not properly respond after a period of time, or established connection failed
// because connected host has failed to respond.)"}
case 10060:
// SQL Error Code: 40197
// The service has encountered an error processing your request. Please try again.
case 40197:
// SQL Error Code: 40540
// The service has encountered an error processing your request. Please try again.
case 40540:
// SQL Error Code: 40613
// Database XXXX on server YYYY is not currently available. Please retry the connection later. If the problem persists, contact customer
// support, and provide them the session tracing ID of ZZZZZ.
case 40613:
// SQL Error Code: 40143
// The service has encountered an error processing your request. Please try again.
case 40143:
// SQL Error Code: 233
// The client was unable to establish a connection because of an error during connection initialization process before login.
// Possible causes include the following: the client tried to connect to an unsupported version of SQL Server; the server was too busy
// to accept new connections; or there was a resource limitation (insufficient memory or maximum allowed connections) on the server.
// (provider: TCP Provider, error: 0 - An existing connection was forcibly closed by the remote host.)
case 233:
// SQL Error Code: 64
// A connection was successfully established with the server, but then an error occurred during the login process.
// (provider: TCP Provider, error: 0 - The specified network name is no longer available.)
case 64:
// DBNETLIB Error Code: 20
// The instance of SQL Server you attempted to connect to does not support encryption.
case (int)ProcessNetLibErrorCode.EncryptionNotSupported:
return true;
}
参见完整的source here。
关于c# - SQL Server transient 异常号，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/35630829/