Spatial Management of DataBase
Spatial data management has been an activearea of research in the database field for two decades,with much of the research being focused on develop-ing data structures for storing and indexing spatialdata. However, no commercial database system pro-vides facilities for directly defining and storing spa-tial data, and forniulating queries based on researchconditions on spatial data. We believe the followingare the relevant issues on which near-term researchshould be focused (in the order of decreasing impor-tance and urgency).
First, relational query optimization techniquesneed to be extended to deal with spatial queries,thatis,queries that contain search conditions on spatialpredicates to be developed.
Second, more work needs to be done on experi-mental validation of the relative performance of someof the more promising data structures and indexingstructures proposed thus far, with consideration of amuch broader set of operations than just a few opera-tions that have typically been used in the limited per-formance studies conducted thus far.
Third, it is difficult to build into a single data-base system multiple data structures for spatial index-ing, and all spatial operators that are useful for awide variety of spatial applications,as such, it isdesirable to build a database system so that it will beas easy as possible to extend the system with addi-tional data structures and spatial operators.
翻译:
数据库的空间组织
二十年来空间数据管理一直是数据库研究领域的活跃区,研究的焦点集中在发展存储和索引空间数据的数据结构上。但是,没有商业数据库系统直接为确定和存储空间数据提供设备,明确地表达以空间数据为研究条件的询问。我们相信下列条件是一些相关问题,在这些问题上,应把焦点集中在近期研究,(按照重要程度和迫切程度排列)
第一,关系询问最恰当技术,需要扩展以应付空间询问,也就是说,对包含查询条件的询问,需要得以发展。
第二.对于迄今提出的一些更有希望的数据结构和索引结构有关效率的实验有一效性,需要做更多的工作,还要考虑涉及面很广的一套操作,而不仅仅是迄今进行的‘有限的’效率研究方面被作典型使用的七个操作。
第三,很难在单个数据库系统内加入空间索引的多个数据结构和对十各种各样空间应用有的所有空间操作员。因此建立一个数据库是很理想的,这样将会尽可能容易地用额外的数据结构和空间操作员来扩大此系统。
责任编辑:cyth