如题，转载自：
http://hi.baidu.com/harry_lime/item/10cf2c174853c7ea39cb3042
如何模拟拔盘操作
Linux has a nifty way of allowing disk state modification via /sys/ interface. Very useful when debugging LVM mirroring, disk disaster recovery etc.
To put a SATA disk offline/running:
echo offline > /sys/block/sda/device/state
echo running > /sys/block/sda/device/state
To delete a device (for unplugging):
echo 1 > /sys/block/sda/device/delete
To scan for new devices (hotplugging):echo "0 0 0" >/sys/class/scsi_host/host/scan
2012-03-13 11:02
一个小例子揭示事务日志的工作原理
http://hi.baidu.com/merry6046/item/67e2fba42e13d42d8819d37c
MySQL update多行
http://soulwan.com/一条语句update多行记录/
http://blog.mozilla.org/data/2011/03/22/how-glow-mozilla-org-gets-its-data/