这个问题在我们的生产上已经有很长时间了。成千上万的用户同时尝试连接mysql，并根据需要不断修改数据库，从而在多个数据库上进行查询。
要更改数据库，这就是客户机的功能-

private MySqlConnection Conn;

public void ChangeDatabase(string DatabaseName)
{
    if (Conn.State != ConnectionState.Open)
    {
        Conn.Open();
    }
    Conn.ChangeDatabase(DatabaseName);
}

根据我们的猜测，在某些情况下，当数据库发生更改时，我们会得到例外-
[捕获到的标准异常：mysql.data.mysqlclient.mysqlexception]对用户'---'使用方法'mysql\u native\u password'的主机'.\u.\u'的身份验证失败，消息为：从流读取失败。
这是堆栈跟踪-

Void Trace(System.Exception) [FileName: ; Line:0].
    Void TimerProcess_Elapsed(System.Object, System.Timers.ElapsedEventArgs) [FileName: ; Line:0].
    Void MyTimerCallback(System.Object) [FileName: ; Line:0].
    Void CallCallbackInContext(System.Object) [FileName: ; Line:0].
    Void RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean) [FileName: ; Line:0].
    Void Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean) [FileName: ; Line:0].
    Void CallCallback() [FileName: ; Line:0].
    Void Fire() [FileName: ; Line:0].
    Void FireNextTimers() [FileName: ; Line:0].
    Void AppDomainTimerCallback() [FileName: ; Line:0]. at
    MySql.Data.MySqlClient.Authentication.MySqlAuthenticationPlugin.AuthenticationFailed(Exception ex) at
    MySql.Data.MySqlClient.Authentication.MySqlAuthenticationPlugin.ReadPacket() at
    MySql.Data.MySqlClient.Authentication.MySqlAuthenticationPlugin.Authenticate(Boolean reset) at
    MySql.Data.MySqlClient.NativeDriver.Authenticate(String authMethod, Boolean reset) at
    MySql.Data.MySqlClient.NativeDriver.Open() at
    MySql.Data.MySqlClient.Driver.Open() at
    MySql.Data.MySqlClient.Driver.Create(MySqlConnectionStringBuilder settings) at
    MySql.Data.MySqlClient.MySqlConnection.Open() at
    FSCCClientUploadServiceLive.ProcessClientUpload.TimerProcess_Elapsed(Object sender, ElapsedEventArgs e)
----------------------------------------------------------
Time stamp 18/09/2018 12:25:48.325
Thread details 27
Message:    [InnerException] Reading from the stream has failed.
Detail: [Source] MySql.Data
Stack Trace:
    Void Trace(System.Exception) [FileName: ; Line:0].
    Void TimerFinish_Elapsed(System.Object, System.Timers.ElapsedEventArgs) [FileName: ; Line:0].
    Void MyTimerCallback(System.Object) [FileName: ; Line:0].
    Void CallCallbackInContext(System.Object) [FileName: ; Line:0].
    Void RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean) [FileName: ; Line:0].
    Void Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean) [FileName: ; Line:0].
    Void CallCallback() [FileName: ; Line:0].
    Void Fire() [FileName: ; Line:0].
    Void FireNextTimers() [FileName: ; Line:0].
    Void AppDomainTimerCallback() [FileName: ; Line:0].
       at MySql.Data.MySqlClient.MySqlStream.LoadPacket()
   at MySql.Data.MySqlClient.MySqlStream.ReadPacket()
   at MySql.Data.MySqlClient.Authentication.MySqlAuthenticationPlugin.ReadPacket()
----------------------------------------------------------
Time stamp 18/09/2018 12:25:49.093
Thread details 27
Message:    [InnerException] Attempted to read past the end of the stream.
Detail: [Source] MySql.Data
Stack Trace:
    Void Trace(System.Exception) [FileName: ; Line:0].
    Void TimerFinish_Elapsed(System.Object, System.Timers.ElapsedEventArgs) [FileName: ; Line:0].
    Void MyTimerCallback(System.Object) [FileName: ; Line:0].
    Void CallCallbackInContext(System.Object) [FileName: ; Line:0].
    Void RunInternal(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean) [FileName: ; Line:0].
    Void Run(System.Threading.ExecutionContext, System.Threading.ContextCallback, System.Object, Boolean) [FileName: ; Line:0].
    Void CallCallback() [FileName: ; Line:0].
    Void Fire() [FileName: ; Line:0].
    Void FireNextTimers() [FileName: ; Line:0].
    Void AppDomainTimerCallback() [FileName: ; Line:0].
       at MySql.Data.MySqlClient.MySqlStream.ReadFully(Stream stream, Byte[] buffer, Int32 offset, Int32 count)
   at MySql.Data.MySqlClient.MySqlStream.LoadPacket()

这个问题不是经常出现的。一切正常的时候，它突然突然冒了出来。
我已经尝试了其他的解决方案，所以对这个，但没有一个是帮助我们。正如我所猜测的，这个异常主要出现在数据库发生变化的场景中。