SIGMOD'04 - Research: Peer-to-Peer and Sensor Networks Efficient Query Reformulation in Peer Data Management Systems Igor Tatarinov Alon Y. Halevy The Price of Validity in Dynamic Networks Mayank Bawa Aristides Gionis Hector Garcia-Molina Rajeev Motwani Compressing Historical Information in Sensor Networks Antonios Deligiannakis Nick Roussopoulos Yannis Kotidis Return to SIGMOD'04 Sessions ©2005 Association for Computing Machinery