salesforce.com cron

Time-based workflows in salesforce currently execute relative to a time. For example, you can use them to to schedule a task for the case owner to follow up with the customer two days after a
case is closed.

It's not currently possible to schedule time-based workflows to execute at a particular time every day - like a cron job would. For that, we'd need to add some secret sauce to time-based workflows.

The Apex trigger below will populate a custom DateTime field called Midnight_Local_Time__c with, you guessed it, midnight - local time for the running user. In conjunction with a time-based workflow, this trigger would allow you to do things like lock all 'Closed' Case records at midnight

trigger Case_PopulateMidnightLocalTime on Case (after update)
{
 List  cases = new List();
 for(Case c : [SELECT CreatedDate FROM Case WHERE Id IN :Trigger.new AND IsClosed = true AND Midnight_Local_Time__c = null])
 {
    CaseTriggerHelper.SetMidnightTime(c, c.CreatedDate);

    cases.add(c);
 }

 update cases;
}

public static void SetMidnightTime(Case c, DateTime dt)
{
 // SFDC defaults 'Midnight' to the 'Time' for this call to newInstance();
 DateTime midnightLocalTime = DateTime.newInstance(dt.year(), dt.month(), dt.day());
 midnightLocalTime = midnightLocalTime.addDays(1).addMinutes(-1);
 c.Midnight_Local_Time__c = midnightLocalTime;
}

If you use this, you'll want to keep in mind that there are limitations around time-based workflows and triggers though:

• Time-based workflows aren't guaranteed to execute exactly on time, there could be a significant delay in their execution.


• Unlimited Edition is limited to 20,000 time triggers per org


• Enterprise Edition is limited to 10,000 time triggers per org

Linvio's CronKit appears to be a useful solution to this problem as well.