Amazon Redshift will no longer support the use of Python UDFs after June 30, 2026. We will start enforcing it in phases. For more information on the details of Python end of life and migration options, 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/) that was published on June 30, 2025. 

# ST\_Polygon
<a name="ST_Polygon-function"></a>

ST\_Polygon returns a polygon geometry whose outer ring is the input linestring with the value that was input for the spatial reference system identifier (SRID). 

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

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

```
ST_Polygon(linestring, srid)
```

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

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

 *srid*   
A value of data type `INTEGER` that represents a SRID. 

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

`GEOMETRY` of subtype `POLYGON`.

The SRID value of the returned geometry is set to *srid*. 

If *linestring* or *srid* is null, then null is returned.

If *linestring* is not a linestring, then an error is returned.

If *linestring* is not closed, then an error is returned.

If *srid* is negative, then an error is returned.

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

The following SQL constructs a polygon with an SRID value. 

```
SELECT ST_AsEWKT(ST_Polygon(ST_GeomFromText('LINESTRING(77.29 29.07,77.42 29.26,77.27 29.31,77.29 29.07)'),4356));
```

```
st_asewkt
-------------
 SRID=4356;POLYGON((77.29 29.07,77.42 29.26,77.27 29.31,77.29 29.07))
```