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Crosses (spatial predicate)

True when geometries cross each other in a way that creates an intersection of lower dimension (commonly for lines).

Category: Topology · Also known as: ST_Crosses, crosses predicate

Definition (expanded)

Crosses is most commonly used with LineStrings (roads crossing rivers, etc.). For polygons, crosses is less common than intersects/overlaps. If your workflows include boundaries as lines, crosses is a useful relationship to detect true crossings rather than touching endpoints.

Examples

PostGIS crosses

SQL

SELECT ST_Crosses(a.geom, b.geom) FROM a, b;