How to Execute the Batch Apex Class for Every 30 minutes?

We can achieve using System.schedule method.

Below is the Example – we need to execute this from the system log or anonymous apex section of the IDE:

batchApexMethod exeClass = new batchApexMethod();

String cronStr = '0 0,30 * * * *';

System.schedule('Process Accs Job', cronStr, exeClass);




for More info you can check using below link

http://www.salesforce.com/us/developer/docs/apexcode/Content/apex_scheduler.htm




Read more »