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\$1AsGeoJSON
<a name="ST_AsGeoJSON-function"></a>

ST\$1AsGeoJSON returns the GeoJSON representation of an input geometry or geography. For more information about GeoJSON, see [GeoJSON](https://en.wikipedia.org/wiki/GeoJSON) in Wikipedia.

For 3DZ and 4D geometries, the output geometry is a 3DZ projection of the input 3DZ or 4D geometry. That is, the `x`, `y`, and `z` coordinates are present in the output. For 3DM geometries, the output geometry is a 2D projection of the input 3DM geometry. That is, only `x` and `y` coordinates are present in the output.

For input geographies, ST\$1AsGeoJSON returns the GeoJSON representation of an input geography. The coordinates of the geography are displayed using the specified precision. 

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

```
ST_AsGeoJSON(geo)
```

```
ST_AsGeoJSON(geo, precision)
```

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

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

 *precision*   
A value of data type `INTEGER`. For geometries, the coordinates of *geo* are displayed using the specified precision 1–20. If *precision* is not specified, the default is 15. For geographies, the coordinates of *geo* are displayed using the specified precision. If *precision* is not specified, the default is 15.

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

`VARCHAR`

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

If *precision* 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_AsGeoJSON-function-examples"></a>

The following SQL returns the GeoJSON representation of a linestring. 

```
SELECT ST_AsGeoJSON(ST_GeomFromText('LINESTRING(3.141592653589793 -6.283185307179586,2.718281828459045 -1.414213562373095)'));
```

```
st_asgeojson
----------------------------------------------------------------------------------------------------------------
 {"type":"LineString","coordinates":[[3.14159265358979,-6.28318530717959],[2.71828182845905,-1.41421356237309]]}
```

The following SQL returns the GeoJSON representation of a linestring. The coordinates of the geometries are displayed with six digits of precision. 

```
SELECT ST_AsGeoJSON(ST_GeomFromText('LINESTRING(3.141592653589793 -6.283185307179586,2.718281828459045 -1.414213562373095)'), 6);
```

```
st_asgeojson
-----------------------------------------------------------------------------
  {"type":"LineString","coordinates":[[3.14159,-6.28319],[2.71828,-1.41421]]}
```

The following SQL returns the GeoJSON representation of a geography. 

```
SELECT ST_AsGeoJSON(ST_GeogFromText('LINESTRING(110 40, 2 3, -10 80, -7 9)'));
```

```
                             st_asgeojson
----------------------------------------------------------------------
 {"type":"LineString","coordinates":[[110,40],[2,3],[-10,80],[-7,9]]}
```