Aggregate queries semantic with spatial relation constraints in spatio-temporal database
Xin Liu · Cehui kexue · 2009
A vast amounts of spatial and temporal data are stored in a spatio-temporal database.So it is very difficult to study on the individual entry in the database.Study of set of tuples with same spatio-temporal characteristics and generating its aggregate information is more useful than individually analyzing every entry.Aggregate information obtained by aggregate queries with spatial relation constraints summarized the varying trends of tuples set are very important to make decision.Based on aggregate queries theory,aggregate queries with spatial relation constraints including the topological relation,direction relation,distance relation and position relation,are studied in the spatial-temporal database.Semantics of aggregate queries with stated spatial relation constrains with the given tuple in given time are studied in the paper.