Amazon Redshift will no longer support the creation of new Python UDFs starting Patch 198. Existing Python UDFs will continue to function until June 30, 2026. For more information, see the [ blog post ](https://aws.amazon.com/blogs/big-data/amazon-redshift-python-user-defined-functions-will-reach-end-of-support-after-june-30-2026/). 

# ST\$1PointN
<a name="ST_PointN-function"></a>

ST\$1PointN returns a point in a linestring as specified by an index value. Negative index values are counted backward from the end of the linestring, so that -1 is the last point. 

The dimension of the returned geometry is the same as that of the input geometry.

## Syntax
<a name="ST_PointN-function-syntax"></a>

```
ST_PointN(geom, index)
```

## Arguments
<a name="ST_PointN-function-arguments"></a>

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

 *index*   
A value of data type `INTEGER` that represents the index of a point in a linestring. 

## Return type
<a name="ST_PointN-function-return"></a>

`GEOMETRY` of subtype `POINT`. 

The spatial reference system identifier (SRID) value of the returned geometry is set to 0. 

If *geom* or *index* is null, then null is returned. 

If *index* is out of range, then null is returned. 

If *geom* is empty, then null is returned. 

If *geom* is not a `LINESTRING`, then null is returned. 

## Examples
<a name="ST_PointN-function-examples"></a>

The following SQL returns an extended well-known text (EWKT) representation of a six-point `LINESTRING` to a `GEOMETRY` object and returns the point at index 5 of the linestring. 

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

```
st_asewkt
-------------
 SRID=4326;POINT(0 5)
```