Concurrency Control in R-trees
نویسنده
چکیده
The nature and types of information in a dynamic battle eld environment ranges from georeferenced satellite images and terrain elevation to maps containing terrain features like roads, enemy unit deployment, activities and targets to spatio-temporal objects like logistic, tactical, and collection management plans. E cient processing of queries over such objects in a database requires support of access paths using an e ective multidimensional data structure. While a large body of research exists on multidimensional data structures (grid les, R-trees, hB-trees to name a few), none of them have been fully integrated into any commercial-strength database management system. One of the primary reasons is the lack of e ective techniques to support concurrent access and manipulations to data using these data structures. This paper identi es problems in supporting concurrent operations over multidimensional data structures and sketches solutions in the context of R-trees. R-tree is a popular multidimensional data structure that has been incorporated into Illustra data management system and has also been implemented as part of the Shore object management system.
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