Timed e-mail notification

[kjetilp]

I have a booking system where I want clients to be notified by e-mail 48 hours before their scheduled appointments.

All client data is kept in a MySql database.

How can I make a script that scans the database every 15 minutes and notifies the clients?

[liquorvicar]

yes but it depends on what OS you're on. if you're on *nix, investigate CRON. on Windoze it's probably the task scheduler or something like that (sorry, not familiar with Windows servers).

[kjetilp]

It's *nix, and I'm investigating crontab now.

I'm completely new to this. Could you tell me how I communicate with cron from phpscripts?

[liquorvicar]

you can run PHP scripts using the CLI version of PHP. put something like this in your crontab:
/15 * php -q yourscript.php
this will run yourscript.php every 15 minutes

[kjetilp]

Thanks! I'm almost there now.

What does php and -q do in your example?

I would like to read more about the file format but 'man 5 crontab' doesn't work on the server.

[liquorvicar]

not really PHP questions these but i'll answer as it's something i've done a bit of.
crontab man page

php -q is the command line PHP command (CLI)
PHP CLI
-q is the 'quiet' switch which means it doesn't output any headers.
if you are logged in as the correct user:
crontab -e
will open your crontab for editing
/15 *
means execute the following command every 15 minutes

happy cron-ing