Hi Plaban,
that's a preferred way of how HR triggers can be configured. Other links may help you as well:
Understanding HR Triggers in Access Control 10.0 - Governance, Risk and Compliance - SCN Wiki
Example of decision table for GRC 10 HR Trigger rule, using BRF+ tool
GRC Access Control - Compliant User Provisioning: HR Triggers
Debugging HR Trigger - GRAC_HR_TRIGGER_EVENT_RECIEVER
Debugging HR Trigger - Simulation
Debugging HR Trigger - PA40 changes to infotypes
Copy & paste from SAP GRC Access Control - Useful Documents, Blogs, Resources, etc..
Best regards,
Alesandro