Syntactical and Semantical Correctness of Pictorial Queries for GIS

One of the main topics in geographical information systems (GIS) research concerns the definition of high level visual query languages (Chrisman, 2002; Laurini & Thompson, 1992). This arises from the need to provide the user with a visual interactive tool for data manipulation and retrieval that is independent of the data’s physical organization. The use of standard query languages for spatial data handling (Rigaux, Scholl, & Voisard, 2001; Shekhar et al. 1999) has been hindered by the lack of appropriate language support. In fact, in visual query languages for GIS, a query can lead to multiple interpretations (Favetta & Aufaure-Portier, 2000).