mysqlplus 是比 ruby mysql 更好的适配器吗？
我想知道 mysqlplus gem 是否是比常见的 Ruby mysql 宝石？我的 Rails 应用程序曾经遇到过一些问题，例如： ActiveRecord::StatementInvalid: Mysql::Error: MySQL 服务器已消失
I want to know if the mysqlplus gem is a better database driver than the common Ruby mysql gem? I used to have some problems in my Rails application, like:
ActiveRecord::StatementInvalid: Mysql::Error: MySQL server has gone away
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MySQL 服务器已经消失意味着 mysql 服务器在运行您的查询时崩溃了，或者（更常见的是）您向其发送了大于 max_allowed_packet 的查询。参见http://dev.mysql.com/doc /refman/5.1/en/packet-too-large.htmlMySQL server has gone awaymeans either the mysql server has crashed running your query or (more commonly) you sent it a quert that is larger than max_allowed_packet. see http://dev.mysql.com/doc/refman/5.1/en/packet-too-large.html如果您只想检查“mysql 服务器已消失”错误，那么 activerecord 就足够了。它是一个成熟的代码库，足以满足大多数用例。
签出 http ://blog.new-bamboo.co.uk/2010/4/11/automatic-reconnection-of-mysql-connections-in-active-record 了解更多详细信息。
当您需要并发时，mysqlplus 会更好，所有酷男孩都推荐它:-)
但我不确定它是否已准备好生产。
if you want to only check for 'mysql server has gone away' errors then activerecord is more than sufficient. it is a mature codebase, good enough for most usecases.
checkout http://blog.new-bamboo.co.uk/2010/4/11/automatic-reconnection-of-mysql-connections-in-active-record for more details.
mysqlplus is better when you need concurrency, all the cool boys recommend it :-)
but i am not sure if it is production ready.
mysql 在一段时间不活动后获取连接。这是在“wait_timeout”中定义的。
可以通过以下方式在 mysql 中看到这一点：
mysql>显示“wait_timeout”等变量，
默认为 8 小时。您收到此错误是因为您已经建立了连接，并且在此期间没有通过该连接执行任何查询。
Activerecord 有 ActiveRecord::Base#verify_active_connections！对于这个用例。
如果您在database.yml中指定reconnect: true，它将自动执行此操作。
当我们从连接池中检出连接时，会执行上述方法，它可以防止不活动。
如果你正在运行一个长时间运行的查询并且它超过了 wait_timeout 期限，那么你可能必须增加 mysql 中的超时变量。您也可以尝试将补丁设置为：
http://gist.github.com/238999 这将重试此类错误、情况的查询可能已更改，但补丁并不可靠，因为它没有重试计数。
mysql reaps the connections after a period of inactivity. this is defined in 'wait_timeout'.
Can see this in mysql by:
mysql> show variables like 'wait_timeout'
by default it is 8 hours. you are getting this error as you have established a connection and there have been no queries executed over this connection for this period.
Activerecord has ActiveRecord::Base#verify_active_connections! for this usecase.
if you specify reconnect: true in database.yml it will do this automatically.
The above method is executed when we checkout a connection from the connection-pool, it guards against inactivity.
It will not help you if you are running a long-running query and it exceeds the wait_timeout period, Then you may have to increase the timeout variable in mysql. You may also try setting the patch in:
http://gist.github.com/238999 This will retry the query on such a error, circumstances may have changed, but the patch is not robust as it does not have a retry count.