With the development of ever-expanding wireless sensor networks (WSNs) that are meant to connect physical worlds with human societies, gathering sensory data at a single point is becoming less and less practical. Unfortunately, the alternative in-network data management schemes may fail to operate in the face of communication voids (or holes) in WSNs (especially 3D WSNs). In response to this challenge, we propose harmonic quorum systems (HQSs) as a lightweight data management system for 2D/3D WSNs. HQSs innovate in exploiting a few scalar fields (constructed using pure localized algorithms) to guide data accesses. This liberates HQSs from depending on any routing mechanisms or location services, hence making HQSs efficient and robust against anomalies in WSN topologies. We implement HQSs in TinyOS, and we perform intensive simulations using TOSSIM to validate the performance of HQSs.