Best way to automate checking record with specific criteria for every 15 minutes?

Question

What is the best possible way to check record that match with my criteria and update it? i have try using scheduled jobs that run every 15 minutes but sometimes it run sometimes it doesn't run. it seems it will run depend on available resource

Here scheduled apex code

global class CallQueueLeadChecker implements Schedulable {
Datetime dtNow = system.now();

global void execute(SchedulableContext SC){
checkLead();
}

public void checkLead(){
    List<Lead> leadList = [SELECT Id,Active_Call_Queue2__c  FROM Lead WHERE Active_Call_Queue2__c = FALSE AND No_Call_Queue__c = FALSE AND (NOT Phone LIKE '%wrong%') AND (NOT Phone LIKE '%invalid%') AND (NOT MobilePhone LIKE '%wrong%') AND (NOT MobilePhone LIKE '%invalid%') AND (Phone !=null OR MobilePhone !=null) AND (Status='Open' OR Status = 'Contacted') AND Picked_By__c=null AND Is_Picked__c = FALSE AND (Last_Open_Timestamp_Formula__c <: dtNow OR Last_Open_Timestamp_Formula__c = NULL) ORDER BY Hubspot_Score__c DESC NULLS LAST LIMIT 200];
    for(Lead l : leadList){
        l.Active_Call_Queue2__c = TRUE;
    }
    update leadList;
  }
}

These are the cron jobs to run schedule apex every 15 minutes

System.schedule('Call Queue Checker 0', '0 0 * * * ?', new CallQueueLeadChecker());
System.schedule('Call Queue Checker 15', '0 15 * * * ?', new CallQueueLeadChecker());
System.schedule('Call Queue Checker 30', '0 30 * * * ?', new CallQueueLeadChecker());
System.schedule('Call Queue Checker 45', '0 45 * * * ?', new CallQueueLeadChecker());

Regards, Brian

Answer 1

There is no way to schedule anything on the dot, scheduled job is the closest you can get, but as you said it won't be guaranteed that it'll run exactly on the 15th minute.

but sometimes it run sometimes it doesn't run.

• It will always run, but not necessarily at the scheduled time, a little bit later.

If it's time critical, you might need to run a scheduled job on an external server where it's guaranteed it'll run there and then, and perform the check/update the record in Salesforce via the API.