Area Queries Based on Voronoi Diagrams

The area query, to find all elements contained in a specified area from a certain set of spatial objects, is a very important spatial query widely required in various fields. A number of approaches have been proposed to implement this query, the best known of which is to obtain a rough candidate set through spatial indexes and then refine the candidates through geometric validations to get the final result. When the shape of the query area is a rectangle, this method has very high efficiency. However, when the query area is irregular, the candidate set is usually much larger than the final result set, which means a lot of redundant detection needs to be done, thus the efficiency is greatly limited. In view of this issue, we propose a method of iteratively generating candidates based on Voronoi diagrams and apply it to area queries. The experimental results indicate that with our approach, the number of candidates in the process of area query is greatly reduced and the efficiency of the query is significantly improved.