7z command to compress file with date as file name

It is one step of my backup script under Windows 2000. Of course it works under Windows XP.
First, I use 7z as my default compress tool. Not because of it is a free, Open Source software, but it supports more format and compress methods.
The command program is 7z.exe under the installation of 7z package.
You can download it from here.


I use it in my daily backup script. So, the file name is contain date information.

7z a %DATE:~-4%-%DATE:~4,2%-%DATE:~7,2%.7z *.sql

The output file name looks like:

2009-05-26.7z

The original file is a MySQL database exporting file. So the name is *.sql.
a means add files into 7z file.
I don’t use method switch. The default is LZMA.
I give you an example. I have a database sql file about 184MB. The compressed file made by above command is 31MB. Very tiny.