Amazon Redshift will no longer support the creation of new Python UDFs starting November 1, 2025.
If you would like to use Python UDFs, create the UDFs prior to that date.
Existing Python UDFs will continue to function as normal. For more information, see the
blog post
ST_NPoints
ST_NPoints returns the number of nonempty points in an input geometry or geography.
Syntax
ST_NPoints(geo)
Arguments
- geo
-
A value of data type
GEOMETRYorGEOGRAPHY, or an expression that evaluates to aGEOMETRYorGEOGRAPHYtype.
Return type
INTEGER
If geo is an empty point, then 0 is returned.
If geo is null, then null is returned.
Examples
The following SQL returns the number of points in a linestring.
SELECT ST_NPoints(ST_GeomFromText('LINESTRING(77.29 29.07,77.42 29.26,77.27 29.31,77.29 29.07)'));
st_npoints
-------------
4
The following SQL returns the number of points in a linestring in a geography.
SELECT ST_NPoints(ST_GeogFromText('LINESTRING(110 40, 2 3, -10 80, -7 9)'));
st_npoints
-------------
4
