Name
ST_Intersects — Tests if two geometries intersect (they have at least one point in common)
Synopsis
boolean ST_Intersects( geometry geomA , geometry geomB );
boolean ST_Intersects( geography geogA , geography geogB );
Descrizione
Returns true if two geometries intersect. Geometries intersect if they have any point in common.
For geography, a distance tolerance of 0.00001 meters is used (so points that are very close are considered to intersect).
In mathematical terms: ST_Intersects(A, B) ⇔ A ⋂ B ≠ ∅
Geometries intersect if their DE-9IM Intersection Matrix matches one of:
-
T******** -
*T******* -
***T***** -
****T****
Spatial intersection is implied by all the other spatial relationship tests, except ST_Disjoint, which tests that geometries do NOT intersect.
![[Note]](../images/note.png)
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Questa funzione incorpora l'uso di una comparazione tra i bounding box in modo da usare qualunque indice spaziale disponibile sulle geometrie. |
Changed: 3.0.0 SFCGAL version removed and native support for 2D TINS added.
Enhanced: 2.5.0 Supports GEOMETRYCOLLECTION.
Enhanced: 2.3.0 Enhancement to PIP short-circuit extended to support MultiPoints with few points. Prior versions only supported point in polygon.
Performed by the GEOS module (for geometry), geography is native
Availability: 1.5 support for geography was introduced.
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For geography, this function has a distance tolerance of about 0.00001 meters and uses the sphere rather than spheroid calculation. |
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NOTE: this is the "allowable" version that returns a boolean, not an integer. |
Questo metodo implementa le OGC Simple Features Implementation Specification for SQL 1.1. s2.1.1.2 //s2.1.13.3 - ST_Intersects(g1, g2 ) --> Not (ST_Disjoint(g1, g2 ))
Questo metodo implementa la specifica SQL/MM. SQL-MM 3: 5.1.27
Questo metodo supporta le Curve e le Circular String.
Questa funzione supporta i Triangoli e le Triangulated Irregular Network Surfaces (TIN).
Geometry Examples
SELECT ST_Intersects('POINT(0 0)'::geometry, 'LINESTRING ( 2 0, 0 2 )'::geometry);
st_intersects
---------------
f
(1 row)
SELECT ST_Intersects('POINT(0 0)'::geometry, 'LINESTRING ( 0 0, 0 2 )'::geometry);
st_intersects
---------------
t
(1 row)
-- Look up in table. Make sure table has a GiST index on geometry column for faster lookup.
SELECT id, name FROM cities WHERE ST_Intersects(geom, 'SRID=4326;POLYGON((28 53,27.707 52.293,27 52,26.293 52.293,26 53,26.293 53.707,27 54,27.707 53.707,28 53))');
id | name
----+-------
2 | Minsk
(1 row)
Geography Examples
SELECT ST_Intersects(
'SRID=4326;LINESTRING(-43.23456 72.4567,-43.23456 72.4568)'::geography,
'SRID=4326;POINT(-43.23456 72.4567772)'::geography
);
st_intersects
---------------
t