ST_CoveredBy - Amazon Redshift

ST_CoveredBy

ST_CoveredBy returns true if the 2D projection of the first input geometry is covered by the 2D projection of the second input geometry. Geometry A is covered by geometry B if both are nonempty and every point in A is a point in B.

ST_CoveredBy(A, B) is equivalent to ST_Covers(B, A).

Syntax

ST_CoveredBy(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's covered by 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 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 first polygon is covered by the second polygon.

SELECT ST_CoveredBy(ST_GeomFromText('POLYGON((0 2,1 1,0 -1,0 2))'), ST_GeomFromText('POLYGON((-1 3,2 1,0 -3,-1 3))'));
st_coveredby ----------- true