Scheduled Apex FAQs

What is Scheduled Apex?

Scheduled Apex is a way to run an Apex class at a specific time or on a recurring schedule.

What is a schedulable interface?

The Schedulable interface is what a class must implement to be scheduled. It has a single method, execute().

What are the methods in a schedulable interface?

The only method is execute(SchedulableContext sc).

What is SchedulableContext?

It is an object that provides context for the scheduled job, similar to BatchableContext.

What is cronTrigger?

CronTrigger is a standard object that stores the scheduling information for a scheduled job, including the cronExpression.

How to know the status and next schedule of the Job that is scheduled?

You can query the CronTrigger and AsyncApexJob objects to get the status and next scheduled run time.

What is cronExpression?

It's a string format that defines the schedule for a job, specifying the time, day, month, etc., using a series of values.

What is System.schedule()?

It's the method used to schedule a class to run at a specified time. It takes three arguments: a job name, a cronExpression, and an instance of the class to be scheduled.

Can we call callouts from a schedule?

Yes, but you must ensure the callout logic is within a method that supports callouts (e.g., a future method or a batch class).

Can we call future methods from Scheduled Apex?

Yes, you can call a future method from the execute method of a scheduled class.

Can we call a batch apex from Scheduled Apex?

Yes, this is a common pattern for processing large amounts of data on a schedule.

Can we manually schedule the apex class?

Yes, you can use System.schedule() to manually schedule a job.

What are the governing limits of Scheduled Apex?

Scheduled Apex runs under the same governor limits as other synchronous Apex.

Good Practices that you have followed?

Keep the execute method simple, often just calling another method or starting a batch job.

Use a meaningful name for the scheduled job.

Monitor the job's status via AsyncApexJob and CronTrigger.

Tell me one best scenario that you have implemented using scheduled apex and you have preferred scheduled apex than manual schedule?

A good example is an automated nightly data synchronization with an external system.

Scheduled Apex is preferred over a manual schedule because it ensures the process runs reliably at the same time every day without human intervention.