Microsoft Office Access v.s. Excel

The Office XP suite provides two different types of database tools.

Access allows you to set up multiple databases that can be related to each other by one or more common fields. Excel allows you to build as many databases as you want, but each one is an island. They can't be related to each other, even if they have a great deal in common; therefore, Access is a relational database application while Excel is a flat-file database - "flat-file" because each database file has a single dimension and doesn't connect to other databases, which would give it depth.

Obviously, if you need to set up a series of databases that work together for reporting purposes - for example, a report that shows all the customers who have purchased a certain product, drwaing data from a Customers database and from a Products database - then Access would be the better choice for you. If you need to set up just one database, or if the databases you intend to build are unrelated, Excel is far simpler to use than Access for most users.

定时关机

　　并不是所有的软件都提供了自动关机功能，比如Windows自带的磁盘碎片整理程序。不过，如果你用的是Win XP/2003，那么在进行磁盘碎片整理时，可以使用Shutdown.exe命令实现定时关机。举个例子，要在3个小时后自动关机，只须在“开始→运行”中键入“Shutdown -s -t 10800”（10800的单位是秒，意即3个小时）。此时，将打开“系统关机”对话框，并显示离关机的时间数。当然，这并不影响其它程序的正常运行。另外，如果要取消自动关机的设置，只须在“开始→运行”中键入“shutdown -a”即可。