ST_NumPoints - Amazon Redshift
SyntaxArgumentsReturn typeExamples
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ST_NumPoints

ST_NumPoints returns the number of points in an input geometry.

Syntax

ST_NumPoints(geom)

Arguments

geom

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

Return type

INTEGER

If geom is null, then null is returned.

If geom is not of subtype LINESTRING, then null is returned.

Examples

The following SQL returns the number of points in the input linestring. 

SELECT ST_NumPoints(ST_GeomFromText('LINESTRING(77.29 29.07,77.42 29.26,77.27 29.31,77.29 29.07)'));

st_numpoints
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4

The following SQL returns null because the input geom is not of subtype LINESTRING. 

SELECT ST_NumPoints(ST_GeomFromText('MULTIPOINT(1 2,3 4)'));

st_numpoints
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