On Spatially Partitioned Temporal Join

This paper presents an innovative partitionbased time join strategy for temporal databases where time is represented by time intervals. The proposed method maps time intervals to points in a two dimensional space and partitions the space into subspaces. Tupies of a temporal relation are clustered into partitions based on the mapping in the space. As a result, when two temporal relations are to be joined over the time attribute, a partition in one relation only needs to be compared with a predetermined set of partitions of the other relation. The mapping scheme and the join algorithms are described. The use of spatial indexing techniques to support direct access to the stored partitions is discussed. The results of a preliminary performance study indicate the efficiency of the proposed method.