2010 IEEE 26th International Conference on Data Engineering (ICDE 2010) (2010)
Long Beach, CA, USA
Mar. 1, 2010 to Mar. 6, 2010
Rajeev Gupta , IBM Research, Delhi, India
Krithi Ramamritham , Indian Institute of Technology, Mumbai, India
Mukesh Mohania , IBM Research, Delhi, India
In this paper we consider triggers over distributed data from various sources such as: “Notify when sale of luxury goods constitute more than 20% of the overall sales”. In such queries client desires to be notified whenever the ratio of two aggregates, over distributed data, crosses the specified threshold. The challenge lies in being able to execute the queries with the minimal amount of communication necessary for update propagation. We address the challenge by proposing schemes for converting the client threshold condition into conditions on individual distributed data sources such that (1) violation of the client threshold occurs only if one or more source conditions are violated (zero false negative), and (2) the number of source violations when client threshold is not violated is small (minimize false positives). Using performance evaluation we show that our algorithms result in up to an order of magnitude less number of false positives compared to the approaches in the literature.
M. Mohania, R. Gupta and K. Ramamritham, "Ratio threshold queries over distributed data sources," 2010 IEEE 26th International Conference on Data Engineering (ICDE 2010)(ICDE), Long Beach, CA, USA, 2010, pp. 581-584.