Abstract

WebGIS applications represent dynamic map information in which users can perform queries on specific attributes that has become popular. However, in practice users may need to do more com-plex queries, for example searching for hotels within a radius of 500m from a specified location. These requirements belong to category of spatial query in GIS. As an contribution to this aspect, The article presents and illustrates some ways to perform spatial queries on Web, including implement-ing on Client side using JSTS JavaScript library, implementing on Server side using WPS or using spatial functions in PostgreSQL/PostGIS spatial database. A WebGIS system - based on the open source Geoserver and OpenLayers v5.3.0 - has been developed and used to perform spatial query for features that have spatial relationships with other features. Experiment result shows that the use of JSTS or WPS or spatial functions in PostgreSQL/PostGIS to perform spatial query over the inter-net is practically doable.