ST_DWithin - Amazon Redshift
SyntaxArgumentsReturn typeExamples
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ST_DWithin

ST_DWithin returns true if the Euclidean distance between the 2D projections of the two input geometry values is not larger than a threshold value.

Syntax

ST_DWithin(geom1, geom2, threshold)

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.

threshold

A value of data type DOUBLE PRECISION. This value is in the units of the input arguments.

Return type

BOOLEAN

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

If threshold is negative, then an error 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 the distance between two polygons is within five units. 

SELECT ST_DWithin(ST_GeomFromText('POLYGON((0 2,1 1,0 -1,0 2))'), ST_GeomFromText('POLYGON((-1 3,2 1,0 -3,-1 3))'),5);

st_dwithin
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 true