Comments on: Scheduling with WordPress Cron Functions

By: jeremyclarke

jeremyclarke — Sat, 19 Dec 2009 00:56:52 +0000

Hey people who are subscribed to this comment thread. Just wanted to point out that in many cases where you're scheduling data saving it might be easier/more effective to use the transients api instead. It allows you to set options similar to update_option() but with a time limit, after which they will be deleted. It's been around a copule of versions but there was no documentation till now: http://codex.wordpress.org/Transients_API

By: tbelknap

tbelknap — Fri, 18 Dec 2009 21:27:18 +0000

Jeremy,

Thanks for that! I'd not seen it before, myself. Very handy for a couple plugins I've got brewin'.

By: tbelknap

tbelknap — Fri, 18 Dec 2009 20:30:03 +0000

One word of caution about the hourly crons: WP will run all the crons whose time has expired once someone actually does cause the WP-cron function to fire. So, if you're not getting hourly visits, hourly crons could have a pretty negative impact on your site performance or do something you didn't expect. Its not a guarantee, just a word of caution.

By: Guillaume

Guillaume — Fri, 18 Dec 2009 20:02:41 +0000

Answered my own question. From the codex:

The action will trigger when someone visits your WordPress site, if the scheduled time has passed.

This is an important nuance. In my case, I need to fetch data from an external site every hour. The first visitor after the scheduled time will see the old data. It will trigger the cron, and only then will the new data be available.

By: Guillaume

Guillaume — Fri, 18 Dec 2009 19:43:01 +0000

Is it a true cron that will start on its own, or on every page load it checks if some job needs to be run?

Another way to put it:
When you set a cron to run every hour and no one visits your site for 3 days, will it run every hour during that time?

By: tbelknap

tbelknap — Sat, 19 Sep 2009 13:57:50 +0000

Thanks for that, Ryan. Not sure, though, that this is exactly the way to do it….

By: Ryan

Ryan — Sat, 19 Sep 2009 13:07:57 +0000

You could simple reschedule the same event as part of your event/function itself if you wanted it to happen FOREVER AND FOREVER!

By: jeremyclarke

jeremyclarke — Wed, 16 Sep 2009 21:59:13 +0000

Diego, that’s also something that can be pretty easily handled entirely by a plugin. Search the plugin repo for ‘backup’ and you’ll find lots of ideas.

By: Thomas Belknap

Thomas Belknap — Wed, 16 Sep 2009 21:45:53 +0000

If by automatic export you’re referring to backing up your posts or database, you’re definitely looking in the wrong area. Something like that needs to be handled by an actual Cron job on the server, which WP Cron does not do. If you don’t have access to the server directly, you might want to check with your web host to see if there is a scheduling tool available to you.

By: deigo

deigo — Wed, 16 Sep 2009 20:15:27 +0000

Hi,
I´m looking for a cron code to do a automatic export…
…anyone knows wath is the function to include it?

thx