Starting from v5.1, you can designate different data to different load generators. For example, an application that is accessed from different geographical locations can have different credentials in each location.
In this case, you can create a test with multiple load generators (agents) in different geographical locations. Then create a dataset with a set of credentials and each credential can have a designation which load generator will consume it.
To do this do the following:
If the Agent cell is left blank then the row will be consumed by all agents.