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\_AsHexWKB
<a name="ST_AsHexWKB-function"></a>

ST\_AsHexWKB returns the hexadecimal well-known binary (WKB) representation of an input geometry or geography using ASCII hexadecimal characters (0–9, A–F). For 3DZ, 3DM, and 4D geometries or geographies, ST\_AsHexWKB uses the Open Geospatial Consortium (OGC) standard value for the geometry or geography type. 

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

```
ST_AsHexWKB(geo)
```

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

 *geo*   
A value of data type `GEOMETRY` or `GEOGRAPHY`, or an expression that evaluates to a `GEOMETRY` or `GEOGRAPHY` type.

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

`VARCHAR`

If *geo* is null, then null is returned.

If the result is larger than a 64-KB `VARCHAR`, then an error is returned. 

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

The following SQL returns the hexadecimal WKB representation of a polygon in a geometry. 

```
SELECT ST_AsHexWKB(ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326));
```

```
st_ashexwkb
--------------------------------
01030000000100000005000000000000000000000000000000000000000000000000000000000000000000F03F000000000000F03F000000000000F03F000000000000F03F000000000000000000000000000000000000000000000000
```

The following SQL returns the hexadecimal WKB representation of a polygon in a geography. 

```
SELECT ST_AsHexWKB(ST_GeogFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))'));
```

```
st_ashexwkb
--------------------------------
01030000000100000005000000000000000000000000000000000000000000000000000000000000000000F03F000000000000F03F000000000000F03F000000000000F03F000000000000000000000000000000000000000000000000
```