Ruby TinyTds gem 编码错误会阻止所有未来对数据库的访问

如何解决Ruby TinyTds gem 编码错误会阻止所有未来对数据库的访问

项目详情：

Ruby 1.8.7
tiny_tds gem 版本 0.6.0.rc1
连接到 microsoft sql 2017
ActiveRecord 版本 2.3.14

我们遇到的问题是我们正尝试通过 rake 任务导出大约 150 万条记录。我遍历每条记录，然后将其导出到 json。一些数据已有 15 年的历史，一张表有一些奇怪的 sql_latin1_General_CP1_CI_AS 字符会破坏 tiny_tds。但最终会发生的事情是，如果我用错误的编码创下了记录（不是很多，在 150 万个中，我认为只有大约 9,000 个），那么此后的每一次迭代都会导致一个奇怪的 ActiveRecord/TinyTds 错误。

这是一个特定的列。我的解决方案是捕获错误，并将记录的 id 报告到文件中，代码如下：

association_names.to_a.each do |association_name|
  puts "Exporting '#{association_name}' from '#{record.class} - #{record.id}'"
  # associations = record.send(association_name).to_a
  associations = begin
    record.send(association_name).to_a
  # rescue TinyTds::Error => e
  rescue ActiveRecord::StatementInvalid => e
    puts "HIT THE TINYTDS ERROR"
    puts "#{e.class}: #{e.message}"
    puts e.backtrace.join("\n")
    File.open(File.join(pack_path,"overflow_errors.txt"),'a') do |f|
      f.puts("Exporting '#{association_name}' from '#{record.class} - #{record.id}'")
    end
    []
  rescue StandardError => e
    puts "HIT THE STANDARD ERROR"
    puts "#{e.class}: #{e.message}"
    puts e.backtrace.join("\n")
    []
  end

  associations.each do |association_record|
    export_record(association_record,pack_path,scp)
  end
end

它抛出错误的地方是record.send(association_name)。第一个错误是 ActiveRecord::StatementInvalid: TinyTds::Error: Buffer overflow converting characters from client into server's character set。我抓住，报告，然后跳到下一个。但是，当发生这种情况时，每个后续记录（没有编码问题的记录，我已经确认），我得到 ActiveRecord::StatementInvalid: NoMethodError: undefined method each' for false:FalseClass`。我能够在控制台中重新创建错误，您可以在下面看到：

>> Service.find(33333).service_details
=> []
>> ServiceData.find(444444).service_data # Record with bad encoding
ActiveRecord::StatementInvalid: TinyTds::Error: Buffer overflow converting characters from client into server's character set
        from /home/my_user/the_project/lib/rails/002_active_record/connection_adapters/abstract_adapter.rb:174:in `log'
        from /home/my_user/the_project/lib/rails/002_active_record/connection_adapters/sqlserver_adapter.rb:657:in `raw_select'
        from /home/my_user/the_project/lib/rails/002_active_record/connection_adapters/sqlserver_adapter.rb:632:in `select'
        from /home/my_user/the_project/lib/rails/002_active_record/connection_adapters/abstract/database_statements.rb:7:in `select_all'
        from /home/my_user/the_project/lib/rails/002_active_record/zbase.rb:489:in `find_by_sql'
        from /home/my_user/the_project/lib/rails/002_active_record/zbase.rb:1360:in `find_every'
        from /home/my_user/the_project/lib/rails/002_active_record/zbase.rb:1395:in `find_one'
        from /home/my_user/the_project/lib/rails/002_active_record/zbase.rb:1381:in `find_from_ids'
        from /home/my_user/the_project/lib/rails/002_active_record/zbase.rb:437:in `find'
        from (irb):4
        from :0
>> Service.find(33333).service_details
/home/my_user/the_project/lib/rails/002_active_record/connection_adapters/sqlserver_adapter.rb:659: warning: TinyTds: dbsqlsend() returned FAIL.

ActiveRecord::StatementInvalid: NoMethodError: undefined method `each' for false:FalseClass
        from /home/my_user/the_project/lib/rails/002_active_record/connection_adapters/abstract_adapter.rb:174:in `log'
        from /home/my_user/the_project/lib/rails/002_active_record/connection_adapters/sqlserver_adapter.rb:657:in `raw_select'
        from /home/my_user/the_project/lib/rails/002_active_record/connection_adapters/sqlserver_adapter.rb:632:in `select'
        from /home/my_user/the_project/lib/rails/002_active_record/connection_adapters/abstract/database_statements.rb:7:in `select_all'
        from /home/my_user/the_project/lib/rails/002_active_record/zbase.rb:489:in `find_by_sql'
        from /home/my_user/the_project/lib/rails/002_active_record/zbase.rb:1360:in `find_every'
        from /home/my_user/the_project/lib/rails/002_active_record/zbase.rb:1395:in `find_one'
        from /home/my_user/the_project/lib/rails/002_active_record/zbase.rb:1381:in `find_from_ids'
        from /home/my_user/the_project/lib/rails/002_active_record/zbase.rb:437:in `find'
        from (irb):5
        from :0

我无法弄清楚为什么会发生这种情况。当 TinyTds::Error 发生时（由于某种原因只能用 ActiveRecord::StatementInvalid 捕获），它似乎锁定了数据库。同样，当我运行 rake 任务时，当发生后一个错误时，我也会收到此警告：warning: TinyTds: dbsqlsend() returned FAIL.。

我已经深入研究了 activerecord 代码，它有时似乎确实返回 false，而不是一个空数组。我尝试更改它，但这导致了一系列其他问题。然而这个错误在生产中从未发生过，因为我们使用一个可以处理这种编码的 asp 服务器来提供这些数据。什么可能导致这种情况？谢谢。