Optimization of geofield queries

In spatial analysis object- and field-oriented representations of spatial entities are needed. Geoobjects are used to model discrete entities such as districts or roads and geofields for continuous phenomena such as air pollution or temperature over a given region. The term geofield query denotes a query regarding geofields. This paper addresses geofield query processing by introducing: (a) PNR representation - relational representation of geofields and geoobjects based on Peano N space-filling curve and relation-valued attributes, (b) Peano algebra - a set of operations extending relational algebra with operations for processing geofields and geoobjects in PNR representation, and (c) geofield queries optimization rules. Presented Peano algebra and optimization rules made it possible to evaluate geofield queries much faster than in classical raster representation.