以下是来自 mysql2 gem页面的引用：

是啊......但为什么？

有人：Dude，Mysql gem works
fiiiiiine。

我：确实如此，但它只交出
你无和字符串的字段值。
让你将它们转换为
在Ruby-land中适当的Ruby类型 - 其中
的速度慢于球。

某人：OK很好，但do_mysql可以
已经给我返回的值与Ruby
对象映射到MySQL类型。

我：是的，但它的API是相当
更复杂，可以慢两倍。

I used to work with the mysql gem, but often nowadays I hear about the mysql2 gem. Also, it is included in the Gemfile by default in Rails 3.0.x.

What is the difference and advantages of using the mysql2 gem?

Here's a quote from the mysql2 gem page:

Yeah… but why?

Someone: Dude, the Mysql gem works fiiiiiine.

Me: It sure does, but it only hands you nil and strings for field values. Leaving you to convert them into proper Ruby types in Ruby-land - which is slow as balls.

Someone: OK fine, but do_mysql can already give me back values with Ruby objects mapped to MySQL types.

Me: Yep, but its API is considerably more complex and can be ~2x slower.