We consider a moving object database, which keeps track of object locations and supports location-aware queries. Frequent location update to the database can provide high query accuracy but result in heavy consumption on the scarce communication bandwidth and precious object energy, as well as great index maintenance overhead at the server. We propose the use of safe-region: an area in which an object moves without having to send in a location update. The database records safe-regions for objects, instead of their exact locations for query answering and filtering. We propose three schemes to compute the safe-region based on object movement pattern and study the performance and the impact on query precision and cost.