Managing Spatiotemporal Data:2+3 R-tree

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2+3 R-tree

Nascimento et al. in [17] have proposed a solution to the problem of handling objects with open transaction times. The idea is to split the indexing of these objects into two parts: one for two-dimensional points and other for three-dimensional lines. Two-dimensional points store the spatial information about the objects and their corresponding start time. Three- dimensional lines store the historical information about the data. Once the ‘started’ point stored in 2D R-tree becomes closed, a corresponding line is constructed to be stored in the 3D R-tree and the point entry is deleted from the 2D R-tree. It should be understood that both trees are expected to be searched depending on the time stamp at which the query is posed. If the end times for each of the spatial points is known a priori, then the need of a 2-D can be completely eliminated reducing the structure to a 3D R-tree.

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FIGURE 22.9: A R-tree at time T0.

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FIGURE 22.10: A R-tree at time T1. The modified nodes are in dark boxes.

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