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