ST_Touches - Amazon Redshift
SyntaxArgumentsReturn typeExamples
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ST_Touches

ST_Touches returns true if the 2D projections of the two input geometries touch. The two geometries touch if they are nonempty, intersect, and have no interior points in common.

Syntax

ST_Touches(geom1, geom2)

Arguments

geom1

A value of data type GEOMETRY or an expression that evaluates to a GEOMETRY type.

geom2

A value of data type GEOMETRY or an expression that evaluates to a GEOMETRY type.

Return type

BOOLEAN

If geom1 or geom2 is null, then null is returned.

If geom1 and geom2 don't have the same value for the spatial reference system identifier (SRID), then an error is returned.

If geom1 or geom2 is a geometry collection, then an error is returned.

Examples

The following SQL checks if a polygon touches a linestring. 

SELECT ST_Touches(ST_GeomFromText('POLYGON((0 0,10 0,0 10,0 0))'), ST_GeomFromText('LINESTRING(20 10,20 0,10 0)'));

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