Paper Info
Title
Efficient processing of moving collective spatial keyword queries
Abstract
As a major type of continuous spatial queries, the moving spatial keyword queries have been studied extensively. Most existing studies focus on retrieving single objects, each of which is close to the query object and relevant to the query keywords. Nevertheless, a single object may not satisfy all the needs of a user, e.g., a user who is driving may want to withdraw money, wash her car, and buy some medicine, which could only be satisfied by multiple objects. We thereby formulate a new type of queries named the moving collective spatial keyword query (MCSKQ). This type of queries continuously reports a set of objects that collectively cover the query keywords as the query moves. Meanwhile, the returned objects must also be close to the query object and close to each other. Computing the exact result set is an NP-hard problem. To reduce the query processing costs, we propose algorithms, based on safe region techniques, to maintain the exact result set while the query object is moving. We further propose two approximate algorithms to obtain even higher query efficiency with precision bounds. All the proposed algorithms are also applicable to MCSKQ with weighted objects and MCSKQ in the domain of road networks. We verify the effectiveness and efficiency of the proposed algorithms both theoretically and empirically, and the results confirm the superiority of the proposed algorithms over the baseline algorithms.
Year
DOI
Venue
2020
10.1007/s00778-019-00583-8
The VLDB Journal
Keywords
DocType
Volume
Moving query, Collective spatial keyword query, Safe region, Query processing algorithms
Journal
29
Issue
ISSN
Citations 
4
1066-8888
0
PageRank 
References 
Authors
0.34
18
6
Name
Order
Citations
PageRank
Hongfei Xu151.10
Yu Gu220134.98
Yu Sun3253.78
Jianzhong Qi4197.10
Ge YU51313175.88
Xiao-Jie Wang6155.34