The preferred embodiment of the present invention advantageously improves the technique of determining {HEAD ~ a grid index} that is used to locate {TAIL ~ a geometric shape} in a spatial database 
is used to locate
The preferred embodiment of the present invention advantageously improves the technique of determining { HEAD ~ a grid index } that is used to locate { TAIL ~ a geometric shape } in a spatial database
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH REL REL REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH