In this chapter, we have used the Apex code to generate additional data to explore how the platform applies indexes and the use of Batch Apex. It is important to always perform some volume testing even if it is just with at least 200 records to ensure that your Triggers are bulkified. Testing with more than this gives you a better idea of other limitations in your software search, such as query performance and any Visualforce scalability issues.
One of the biggest pitfalls with volume testing is the quality of the test data. It is not often that easy to get hold of actual customer data, so we must emulate the spread of information by varying field values amongst the records to properly simulate how the software will not only behave under load with more records, but under load with a different dispersion of values. This will tease out further bugs that might only manifest if the data values change within a batch of records. For example, the Apex script used in this chapter could...