Delayed distance computations for nearest-neighbor queries in an R-tree index
First Claim
1. In a database system, a computer-implemented method for locating neighboring geometric elements and geographic objects, represented as data geometries stored in the database system, of a query geometry, the method comprising:
- storing in the database data geometries representing geometric elements, geographic objects, or both;
determining a minimum bounding rectangle of the query geometry;
determining a minimum bounding rectangle of each data geometry;
identifying as candidate data geometries those data geometries for which a distance between the minimum bounding rectangle of the query geometry and the minimum bounding rectangle of the data geometry is less than a threshold distance; and
determining a distance between the query geometry and only each candidate data geometry when a number of candidate data geometries equals a threshold number.
1 Assignment
0 Petitions
Accused Products
Abstract
A method for locating neighboring data geometries of a query geometry. A minimum bounding rectangle of the query geometry is determined. A minimum bounding rectangle of each data geometry is determined. Candidate data geometries are identified by determining if a distance between the minimum bounding rectangle of the query geometry and the data geometry is less than a threshold distance. A distance between the query geometry and the candidate data geometry is mathematically calculated when a number of candidate data geometries equals a threshold number or when no more data geometries remain.
-
Citations
19 Claims
-
1. In a database system, a computer-implemented method for locating neighboring geometric elements and geographic objects, represented as data geometries stored in the database system, of a query geometry, the method comprising:
-
storing in the database data geometries representing geometric elements, geographic objects, or both; determining a minimum bounding rectangle of the query geometry; determining a minimum bounding rectangle of each data geometry; identifying as candidate data geometries those data geometries for which a distance between the minimum bounding rectangle of the query geometry and the minimum bounding rectangle of the data geometry is less than a threshold distance; and determining a distance between the query geometry and only each candidate data geometry when a number of candidate data geometries equals a threshold number. - View Dependent Claims (2, 3, 4, 5, 6, 7)
-
-
8. In a database system, a computer-implemented method for comparing geometric elements and geographic objects, represented as data geometries stored in the database system, with a query geometry, the method comprising:
-
storing in the database data geometries representing geometric elements, geographic objects, or both; determining a minimum bounding rectangle of the query geometry; determining a minimum bounding rectangle of each data geometry; identifying candidate data geometries by determining whether data geometries fulfill a first filter condition with respect to the query geometry by comparing the minimum bounding rectangles of each data geometry with the minimum bounding rectangle of the query geometry; continuing the comparing of the minimum bounding rectangle of the query geometry with the minimum bounding rectangles until a number of data geometries that fulfill the first filter condition reaches a threshold value; and comparing the query geometry with each data geometry that fulfills the first filter condition, upon the number of data geometries that fulfill the first filter condition reaching the threshold value. - View Dependent Claims (9, 10, 11, 12, 13, 14, 15, 16, 17)
-
-
18. A computer program product for performing a process of determining relationships among geometric elements and geographic objects represented in a database, comprising:
-
a computer readable medium; and computer program instructions, recorded on the computer readable medium, executable by a processor, for performing the steps of storing in the database data geometries representing geometric elements, geographic objects, or both; determining a minimum bounding rectangle of the query geometry; determining a minimum bounding rectangle of each data geometry; identifying candidate data geometries by determining whether data geometries fulfill a first filter condition with respect to the query geometry by comparing the minimum bounding rectangles of each data geometry with the minimum bounding rectangle of the query geometry; continuing the comparing of the minimum bounding rectangles until a number of data geometries that fulfill the first filter condition reaches a threshold value; and comparing the query geometry with each data geometry that fulfills the first filter condition, upon the number of data geometries that fulfill the first filter condition reaching the threshold value.
-
-
19. A system for performing a process of determining relationships among geometric elements and geographic objects represented in a database, comprising:
-
a processor operable to execute computer program instructions; and a memory operable to store computer program instructions executable by the processor, for performing the steps of; storing in the database data geometries representing geometric elements, geographic objects, or both; determining a minimum bounding rectangle of the query geometry; determining a minimum bounding rectangle of each data geometry; identifying candidate data geometries by determining whether data geometries fulfill a first filter condition with respect to the query geometry by comparing the minimum bounding rectangles of each data geometry with the minimum bounding rectangle of the query geometry; continuing the comparing of the minimum bounding rectangles until a number of data geometries that fulfill the first filter condition reaches a threshold value; and comparing the query geometry with each data geometry that fulfills the first filter condition, upon the number of data geometries that fulfill the first filter condition reaching the threshold value.
-
Specification