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An Incremental Index for Bitemporal Databases

Bitemporal databases record not only the history of tuples in temporal tables, but also record the history of the databases themselves. Indexing structures, which are a critical issue in traditional databases, became even more critical for bitemporal databases. We address this problem by investigating an incremental indexing structure based on R-trees, called the HR-tree, which was originally aimed at spatiotemporal databases. We have found that the HR-tree is much more efficient (up to 80% faster) than previously proposed approaches based on two R-trees when processing transaction time point based queries. As for size, the HR-tree was found to be better suited for medium to large sized batch updates, otherwise it is prone to be quite large.