简介
多维数据库的一种重要的查询类型 -- skyline.
skyline的定义
the skyline S is the set of all points p such that there is no other point q which dominates p
dominate的定义
q is said to dominate p if q is better than p in at least one dimension and not worse than p in all other dimensions.
ADS 验证数据结构
MR-tree 在 VLDB “Authenticated indexing for outsourced spatial databases” 首次提出。综合了MB-tree 和 R* tree.
Node Structure
叶子节点：一个叶子节点包含若干关键字（这里一个关键字是一个points或者data objects）。 叶子节点的摘要由节点里的所有关键字的摘要取串联。
中间节点：一个中间节点的包含若干项，每一项(pi, MBRi, Hi), pi是指针，MBRi是minimum bounding rectangle, Hi是第i个孩子的摘要。The digest summarizes child nodes’ MBRs(MBR1-MBRf ), in addition to their digests (H1−Hf).
Query Processing in MRtreeExample of MR-tree
**粗体** _斜体_ [链接](http://example.com) `代码` - 列表 > 引用。你还可以使用@来通知其他用户。