A design is presented of a customized query language for manipulating geometric objects in a three-dimensional space, called dynamic spatial query language (DSQL), with which an end user retrieves, updates, and deletes spatial and nonspatial information about the objects without any knowledge of their exact spatial locations. DSQL, as an application-oriented query language, is built on top of an object-oriented database system, and operates on a database view that captures spatial characteristics of the objects and relationships among the objects. The authors also describe a bilevel data modeling approach as a methodology for design and implementation application-oriented query languages.
展开▼