Batch Apex

A developer can now employ batch Apex to build complex, long-running processes that run on thousands of records on the Force.com platform. Batch Apex operates over small batches of records, covering your entire record set and breaking the processing down to manageable chunks. For example, a developer could build an archiving solution that runs on a nightly basis, looking for records past a certain date and adding them to an archive. Or a developer could build a data cleansing operation that goes through all Accounts and Opportunities on a nightly basis and updates them if necessary, based on custom criteria.

Batch Apex is exposed as an interface that must be implemented by the developer. Batch jobs can be programmatically invoked at runtime using Apex.

You can only have five queued or active batch jobs at one time. You can evaluate your current count by viewing the Scheduled Jobs page in Salesforce or programmatically using SOAP API to query the AsyncApexJob object.

Use extreme care if you are planning to invoke a batch job from a trigger. You must be able to guarantee that the trigger will not add more batch jobs than the limit. In particular, consider API bulk updates, import wizards, mass record changes through the user interface, and all cases where more than one record can be updated at a time.

Batch jobs can also be programmatically scheduled to run at specific times using the Apex scheduler, or scheduled using the Schedule Apex page in the Salesforce user interface. For more information on the Schedule Apex page, see “Schedule Apex Jobs” in the Salesforce online help.

The batch Apex interface is also used for Apex managed sharing recalculations.

For more information on batch jobs, continue to Using Batch Apex.

For more information on Apex managed sharing, see Understanding Apex Managed Sharing.

• Using Batch Apex
• Batch Apex Governor Limits & Best Practices