| ST_Intersects | Tests whether two geometries share any space in common. Returns true if geometries intersect, false otherwise. Used for identifying overlapping areas. | SELECT a.*, b.* FROM service_areas a JOIN market_zones b ON ST_Intersects(a.geometry, b.geometry); |
| ST_Within | Tests whether one geometry is completely inside another. Returns true if the first geometry is completely within the second geometry. | SELECT a.name, b.name FROM points a JOIN polygons b ON ST_Within(a.geometry, b.geometry); |
| ST_Buffer | Creates a new geometry that represents all points within a given distance from the input geometry. Useful for creating service areas or zones of influence. | SELECT location_id, ST_Buffer(geometry, 5000) as service_area FROM distribution_centers; |
| ST_Centroid | Computes the geometric center (centroid) of a geometry. Returns a point that represents the average position of all points in the geometry. | SELECT region_name, ST_Centroid(geometry) as center_point FROM service_regions; |
| ST_Distance | Calculates the shortest distance between two geometries. Returns the minimum distance between any two points in the two geometries. | SELECT a.id, b.id, ST_Distance(a.geometry, b.geometry) as distance FROM points a CROSS JOIN points b WHERE a.id != b.id; |
| ST_Area | Calculates the area of a polygon geometry. Returns the area in the units of the spatial reference system. | SELECT territory_id, ST_Area(geometry::geography) as area_sqm FROM market_territories; |
| ST_Length | Calculates the length of a linear geometry (linestring). Returns the length in the units of the spatial reference system. | SELECT route_id, ST_Length(geometry::geography) as length_meters FROM delivery_routes; |
| ST_Union | Combines multiple geometries into a single geometry. Dissolves overlapping boundaries and creates a single continuous geometry. | SELECT region_id, ST_Union(geometry) as combined_geometry FROM parcels GROUP BY region_id; |
| ST_Intersection | Returns the geometry representing the shared portions of two geometries. Creates a new geometry containing only the overlapping areas. | SELECT ST_Intersection(a.geometry, b.geometry) as overlap FROM zone_a a CROSS JOIN zone_b b; |
| ST_Transform | Transforms a geometry from one coordinate system to another. Used to convert between different spatial reference systems (SRS). | SELECT id, ST_Transform(geometry, 4326) as wgs84_geom FROM locations; |
| ST_Envelope | Computes the minimum bounding rectangle that contains a geometry. Returns a rectangular polygon that completely encloses the input geometry. | SELECT region_id, ST_Envelope(ST_Collect(geometry)) as bbox FROM market_regions GROUP BY region_id; |
| ST_ConvexHull | Computes the smallest convex polygon that contains all points in a geometry. Creates a shape that represents the outer boundary of a set of points. | SELECT cluster_id, ST_ConvexHull(ST_Collect(geometry)) as boundary FROM points GROUP BY cluster_id; |
| ST_Contains | Tests whether one geometry completely contains another. Returns true if the second geometry is completely contained within the first geometry. | SELECT points.* FROM customer_points points JOIN service_areas areas ON ST_Contains(areas.geometry, points.geometry); |
