ST_Disjoint
Determines if two GEOMETRY objects do not intersect or touch.
If ST_Disjoint returns TRUE for a pair of GEOMETRY objects, ST_Intersects returns FALSE for the same two objects.
GEOGRAPHY Polygons with a vertex or border on the International Date Line (IDL) or the North or South pole are not supported.
Behavior Type
Syntax
ST_Disjoint( g1, g2 [USING PARAMETERS spheroid={true | false}] )
Arguments
g1 |
Spatial object, type GEOMETRY |
g2 |
Spatial object, type GEOMETRY |
Parameters
spheroid = {true | false} |
(Optional) BOOLEAN that specifies whether to use a perfect sphere or WGS84. Default: False |
Returns
BOOLEAN
Supported Data Types
Data Type | GEOMETRY | GEOGRAPHY (WGS84) |
Point |
Yes |
Yes |
Multipoint |
Yes |
No |
Linestring |
Yes |
No |
Multilinestring |
Yes |
No |
Polygon |
Yes |
Yes |
Multipolygon |
Yes |
No |
GeometryCollection |
Yes |
No |
Compatible GEOGRAPHY pairs:
Data Type | GEOGRAPHY (WGS84) |
Point-Point | No |
Linestring-Point | No |
Polygon-Point | Yes |
Multipolygon-Point | No |
Examples
The following examples show how to use ST_Disjoint.
Two non-intersecting or touching polygons:
=> SELECT ST_Disjoint (ST_GeomFromText('POLYGON((-1 2,0 3,0 1,-1 2))'), ST_GeomFromText('POLYGON((1 0, 1 1, 2 2, 1 0))')); ST_Disjoint ------------- t (1 row)
Two intersecting linestrings:
=> SELECT ST_Disjoint(ST_GeomFromText('LINESTRING(-1 2,0 3)'), ST_GeomFromText('LINESTRING(0 2,-1 3)')); ST_Disjoint ------------- f (1 row)
Two polygons touching at a single point:
=> SELECT ST_Disjoint (ST_GeomFromText('POLYGON((-1 2, 0 3, 0 1, -1 2))'), ST_GeomFromText('POLYGON((0 2, 1 1, 1 2, 0 2))')); ST_Disjoint -------------- f (1 row)