For scheduling every 30minutes code will be like below : public class SNO_GVC_DRT_ProcesseBatchScheduler implements Schedulable { //Scheduler public static final Integer BATCH_SIZE = 10; public void execute(SchedulableContext sc) { SNO_GVC_DRT_ProcesseBatch deletegroup = new SNO_GVC_DRT_ProcesseBatch(); Database.executebatch(deletegroup,BATCH_SIZE); Datetime currentTime = System.now().addMinutes(30); // prepare schedule string / settings String scheduleString = String.format( '{0} {1} {2} {3} {4} {5} {6}', new List<String>{ String.valueOf(currentTime.second()), String.valueOf(currentTim...