Multiple Depth DB Tables Indexing on the Sphere
Multiple Depth DB Tables Indexing on the Sphere
复制标题
球体上的多深度数据库表索引
DOI：
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发表时间：
2010
期刊：
影响因子：
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通讯作者：
G. Calderone
中科院分区：
文献类型：
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作者：
L. Nicastro;G. Calderone
任何处理大型天文数据集的项目都应考虑使用关系数据库服务器。如果表格缺乏有效的索引方案，则需要快速选择天空区域、物体交叉匹配和其他涉及天空坐标的高级数据调查的查询可能是不可行的。本文介绍了动态指数工具(DIF)软件包。通过使用HTM和HEALPix天空像素化方案，它允许对存储到MySQL表中的球形数据进行非常高效的索引和管理。DIF可以同时使用任意数量的天空分辨率自动管理托管球面坐标的任何表格。DIF包含一组工具，其中SQL可调用函数在圆形和矩形区域上执行查询。此外，通过消除二维数据索引的限制和困难，DIF允许充分利用关系数据库的能力。报告了对Giga-Entry表的性能测试以及该包的一些实际使用。
Any project dealing with large astronomical datasets should consider the use of a relational database server (RDBS). Queries requiring quick selections on sky regions, objects cross-matching and other high-level data investigations involving sky coordinates could be unfeasible if tables are missing an effective indexing scheme. In this paper we present the Dynamic Index Facility (DIF) software package. By using the HTM and HEALPix sky pixelization schema, it allows a very efficient indexing and management of spherical data stored into MySQL tables. Any table hosting spherical coordinates can be automatically managed by DIF using any number of sky resolutions at the same time. DIF comprises a set of facilities among which SQL callable functions to perform queries on circular and rectangular regions. Moreover, by removing the limitations and difficulties of 2-d data indexing, DIF allows the full exploitation of the RDBS capabilities. Performance tests on Giga-entries tables are reported together with some practical usage of the package.