TinyDB [12] is the pioneer in sensor network database
abstraction developed at University of California Berkeley. Its
sensor software implementation running on each node includes
a schema manager to handle different types of readings and
node properties, a query processor, a small memory manager
and a topology manager for efficient routing. The Java-based
client interface provides functionality to extract information
about the network, build SQL-like queries, inject them into
the network and listen for results. It also provides graphical
user interfaces to construct queries, display sensor results and
visualize network topology. The rich query language, with
extensions for query duration and sample rates lets users
describe the data they want to gather without requiring any
knowledge about how this data might be gathered. Multiple
queries are allowed and managed by a query execution
planning engine. TinyDB also manages the underlying radio
network and ensures relatively reliable data delivery. Finally
low power optimization is also one of the advantageous aspects
of TinyDB. On the other hand TinyDB is based on TinyOS
1.x, supporting no specific in-node processing capabilities