ST_StartPoint - Amazon Redshift
SyntaxArgumentsReturn typeExamples
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ST_StartPoint

ST_StartPoint returns the first point of an input linestring. The spatial reference system identifier (SRID) value of the result is the same as that of the input geometry. The dimension of the returned geometry is the same as that of the input geometry.

Syntax

ST_StartPoint(geom)

Arguments

geom

A value of data type GEOMETRY or an expression that evaluates to a GEOMETRY type. The subtype must be LINESTRING.

Return type

GEOMETRY

If geom is null, then null is returned.

If geom is empty, then null is returned.

If geom isn't a LINESTRING, then null is returned.

Examples

The following SQL returns an extended well-known text (EWKT) representation of a four-point LINESTRING to a GEOMETRY object and returns the start point of the linestring. 

SELECT ST_AsEWKT(ST_StartPoint(ST_GeomFromText('LINESTRING(0 0,10 0,10 10,5 5,0 5)',4326)));

st_asewkt
-------------
 SRID=4326;POINT(0 0)