当 MySQL 必须要进行排序时，就会在从磁盘上读取数据时分配一个排序缓冲区来存放这些数据行。

When MySQL must perform a sort, it allocates a sort buffer to store the rows as they're read from disk.

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当然，但是您将很快看见，在2.4.4，字节缓冲区对象拥有一大堆方便的方法，作为别的基本数据类型用来获取和存放缓冲区内容。

Sure, but as you'll soon see in Section 2.4.4, ByteBuffer objects possess a host of convenience methods for getting and putting the buffer content as other primitive data types.

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数据库也会为服务器进程分配私有的内存空间，这块空间叫做PGA(程序全局区)，那里存放着私有的进程和会话信息。

It will also allocate a private memory area called PGA, where it stores what is private to the process and to the session.

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