want another crontab example?
In this example I am showing you how to use the crontab in order to reload a fresh copy of a DB at 12 noon and 12 midnight everyday. Lets take a look:
SHELL=/bin/sh
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
# m h dom mon dow user command
0 12,0 * * * /usr/bin/mysql -u username -ppassword database_name < ~/backupfile.sql
You can see that I am connecting to mysql with my -u username and -ppassword ( And no, I did not make a mistake by not putting a space in between -ppassword, its supposed to be like that, if you put a space in between it thinks that *space* is part of your password.) and telling it to import the sql file backupfile.sql to the database database_name. This script is good if you need to reload a DB with fresh new data everyday. For example if you have a TEST CRM that people can use and test, you dont want people to input so much junk, so you have to reset the test data ever so often.
I love cron. hes a good friend of mine! 
Awesome… good job explaining this.. its exactly what I was looking for!!