Sample code: SampleSchedulableClass obj = new SampleSchedulableClass(); String cron = ‘0 59 * * * *’ System.schedule(‘Testing’, cron, obj); The above code executes SampleSchedulableClass for every one hour. Syntax for Cron: Seconds Minutes Hours Day Month Week Year Seconds : 0 – 59 Minutes  : 0 – 59 Hours     : 0 – 23 Day … Continue reading System.schedule in Apex scheduler in Salsforce