cron jobs or PHP scheduler

I think your concept needs to change.

PHP cannot schedule a job, neither can MySQL. Triggers in MySQL execute when a mysql query occurs, not at a specific time. Neither

This limitation usually isn't a problem in web development. The reason is because your PHP application should control all data going in and out. Usually, this means just the HTML that displays that data, or other formats to users, or other programs.

In your case you can think about it this way. The deadline is a set date. You can treat it as data, and save it to your database. When the deadline occurs is not important, it is that the data you have sent in your database is viewed correctly.

When a request is made to your application, check if the date of the deadline is in the past, if it is, then display that the project is closed - or update that the project is closed, just before display.

There really is no reason to update data independantly of your PHP application.

Usually, the only things you want to schedule are jobs that would affect your application in terms of load, or that need to be done only once, or where concurrency or time is an issue.

In your case none of those apply.

PS: I haven't tried PHPscheduler but I can guess it isn't a true scheduler. Cron is a deamon that sleeps until a given task is due in its queue, executes the task, then sleeps till the next one is due (at least thats what it does in the current algorithm). PHP cannot do that without the sockets and fork extensions, as special setup. So PHPscheduler is most likely just checking if a date for a task has expired, on each load of a webpage (whenever PHP executes a page). This is no different then you just checking if the date on the project has expired, without the overhead of PHPScheduler.

I would always go for a cron job for anything scheduling related.

The big bonus point is that you can echo info out as well and it get's emailed to you.

You'll find once you start using cronjobs, it's hard to stop.

cron does not exist, per se, in vista, but what does exist is the standard windows scheduling manager which you can run with a command line like "php -q -f myfile.php" which will execute the php file at the given time.

you can also use a port of the cron program, there are many out there.

if it is not critical to the second, any windows scheduling application will do, just be sure to have you PHP bin path in your PATH variable for simplicity.

For Windows CRON jobs I cannot recommend PyCron enough.

While CRON and Windows Scheduled Tasks are the tried and true ways of scheduling jobs/tasks to run on a regular basis, there are use cases where having a different scheduled task in CRON/Windows can become tedious. Namely when you want to let users schedule things to run, or for instances where you prefer simplicity/maintainability/portability/etc or all of the above.

In cases where I prefer to not use CRON/Windows for scheduled tasks, I build into the application a task scheduling system. This still requires 1 CRON job or Windows Task to be scheduled. The idea is to store Job details in the database (job name, job properties, last run time, run interval, anything else that is important for your implementation). You then schedule a "Master" job in CRON or Windows which handles running all of your other jobs for you. You'll need this master job to run at least as often as your shortest interval; if you want to be able to schedule jobs that run every minute the master job needs to run every minute.

You can then launch each scheduled job in the background from PHP with minimal effort (if you want). In memory constrained systems you can monitor memory usage or keep track of the PIDs (various methods) and limit to N jobs running at a given time.

I've had a great deal of success with this method, YMMV however based on your needs and your implementation.