In-database connected component analysis

We describe a Big Data-practical, SQL-implementable algorithm for efficiently determining connected components for graph data stored in a Massively Parallel Processing (MPP) relational database. The algorithm described is a linear-space, randomised algorithm, always terminating with the correct answer but subject to a stochastic running time, such that for any ǫ > 0 and any input graph G = 〈V,E〉 the algorithm terminates after O(log |V |) SQL queries with probability of at least 1− ǫ, which we show empirically to translate to a quasi-linear runtime in practice. Monash University, Melbourne, Australia. Email: [email protected] Monash University and Telstra Corporation, Melbourne, Australia. Email: [email protected] UBS, Zürich, Switzerland. Email: [email protected]