Approximating Aggregation Queries in Peer-to-Peer Networks

B. Arai, G. Das, D. Gunopulos, V. Kalogeraki
2006 22nd International Conference on Data Engineering (ICDE'06)  
Peer-to-peer databases are becoming prevalent on the Internet for distribution and sharing of documents, applications, and other digital media. The problem of answering large scale, ad-hoc analysis queries -e.g., aggregation queries -on these databases poses unique challenges. Exact solutions can be time consuming and difficult to implement given the distributed and dynamic nature of peer-to-peer databases. In this paper we present novel sampling-based techniques for approximate answering of
more » ... hoc aggregation queries in such databases. Computing a high-quality random sample of the database efficiently in the P2P environment is complicated due to several factors -the data is distributed (usually in uneven quantities) across many peers, within each peer the data is often highly correlated, and moreover, even collecting a random sample of the peers is difficult to accomplish. To counter these problems, we have developed an adaptive two-phase sampling approach, based on random walks of the P2P graph as well as block-level sampling techniques. We present extensive experimental evaluations to demonstrate the feasibility of our proposed solution.
doi:10.1109/icde.2006.23 dblp:conf/icde/AraiDGK06 fatcat:uwlpd2a3evf55f3nlizdqkbh6i