The preferred embodiment of the present invention improves techniques of the past that were used to determine the grid cell size and that facilitate {HEAD ~ efficient indexing} of {TAIL ~ a spatial database} 
of
The preferred embodiment of the present invention improves techniques of the past that were used to determine the grid cell size and that facilitate { HEAD ~ efficient indexing } of { TAIL ~ a spatial database }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL