Which index is standard for precise spatial queries over points and polygons in production databases like PostGIS?

Which index is standard for precise spatial queries over points and polygons in production databases like PostGIS?

• A. R-tree
• B. Quadtree
• C. B-tree
• D. Hash index

Answer: (A)

Spatial queries on points and polygons rely on an index that can prune many non-relevant geometries using their bounding bounds. An R-tree style index provides exactly that: it stores geometries in a hierarchical tree of minimum bounding rectangles, so a search can quickly rule out large groups of objects that don’t intersect or aren’t nearby. In production databases like PostGIS, the standard approach is a GiST index that implements an R-tree–like structure for geometry types. This makes predicates such as intersects, contains, and distance efficient on large collections of points and polygons. Other options don’t fit as well: you’d use a B-tree or a Hash index for scalar, exact lookups, not for multi-dimensional spatial predicates; a Quadtree is a different spatial partitioning approach and, while useful in some contexts, is not the default, standard choice in systems like PostGIS.

Spatial queries on points and polygons rely on an index that can prune many non-relevant geometries using their bounding bounds. An R-tree style index provides exactly that: it stores geometries in a hierarchical tree of minimum bounding rectangles, so a search can quickly rule out large groups of objects that don’t intersect or aren’t nearby. In production databases like PostGIS, the standard approach is a GiST index that implements an R-tree–like structure for geometry types. This makes predicates such as intersects, contains, and distance efficient on large collections of points and polygons.

Other options don’t fit as well: you’d use a B-tree or a Hash index for scalar, exact lookups, not for multi-dimensional spatial predicates; a Quadtree is a different spatial partitioning approach and, while useful in some contexts, is not the default, standard choice in systems like PostGIS.