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\$1GeomFromWKB
<a name="ST_GeomFromWKB-function"></a>

ST\$1GeomFromWKB constructs a geometry object from a hexadecimal well-known binary (WKB) representation of an input geometry. 

ST\$1GeomFromWKB accepts 3DZ, 3DM, and 4D geometries written in WKB hexadecimal format.

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

```
ST_GeomFromWKB(wkb_string)
```

```
ST_GeomFromWKB(wkb_string, srid)
```

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

 *wkb\$1string*   
A value of data type `VARCHAR` that is a hexadecimal WKB representation of a geometry.

 *srid*   
A value of data type `INTEGER` that is a spatial reference identifier (SRID). If an SRID value is provided, the returned geometry has this SRID value. Otherwise, the SRID value of the returned geometry is set to 0.

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

`GEOMETRY`

If *wkb\$1string* or *srid* is null, then null is returned. 

If *srid* is negative, then null is returned. 

If *wkb\$1string* is not valid, then an error is returned. 

If *srid* is not valid, then an error is returned. 

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

The following SQL constructs a polygon from a WKB value and returns the WKT representation of a polygon. 

```
SELECT ST_AsText(ST_GeomFromWKB('01030000000100000005000000000000000000000000000000000000000000000000000000000000000000F03F000000000000F03F000000000000F03F000000000000F03F000000000000000000000000000000000000000000000000'));            
```

```
 st_astext
--------------------------------
 POLYGON((0 0,0 1,1 1,1 0,0 0))
```