ST_Within - Amazon Redshift
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ST_Within

ST_Within returns true if the 2D projection of the first input geometry is within the 2D projection of the second input geometry.

For example, geometry A is within geometry B if every point in A is a point in B and their interiors have nonempty intersection.

ST_Within(A, B) is equivalent to ST_Contains(B, A).

Syntax

ST_Within(geom1, geom2)

Arguments

geom1

A value of data type GEOMETRY or an expression that evaluates to a GEOMETRY type. This value is compared with geom2 to determine if it is within geom2.

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 spatial reference system identifier (SRID) value, 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 first polygon is within the second polygon.

SELECT ST_Within(ST_GeomFromText('POLYGON((0 2,1 1,0 -1,0 2))'), ST_GeomFromText('POLYGON((-1 3,2 1,0 -3,-1 3))'));
st_within ----------- true