docs/api/sql/Geometry-Output/ST_AsGeoJSON.md

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# ST_AsGeoJSON

!!!note
	This method is not recommended. Please use [Sedona GeoJSON data source](../../../tutorial/sql.md#save-geojson) to write GeoJSON files.

Introduction: Return the [GeoJSON](https://geojson.org/) string representation of a geometry

The type parameter (Since: `v1.6.1`) takes the following options -

- "Simple" (default): Returns a simple GeoJSON geometry.
- "Feature": Wraps the geometry in a GeoJSON Feature.
- "FeatureCollection": Wraps the Feature in a GeoJSON FeatureCollection.

Format:

`ST_AsGeoJSON (A: Geometry)`

`ST_AsGeoJSON (A: Geometry, type: String)`

Return type: `String`

Since: `v1.0.0`

SQL Example (Simple GeoJSON):

```sql
SELECT ST_AsGeoJSON(ST_GeomFromWKT('POLYGON((1 1, 8 1, 8 8, 1 8, 1 1))'))
```

Output:

```json
{
  "type":"Polygon",
  "coordinates":[
    [[1.0,1.0],
      [8.0,1.0],
      [8.0,8.0],
      [1.0,8.0],
      [1.0,1.0]]
  ]
}
```

SQL Example (Feature GeoJSON):

Output:

```json
{
  "type":"Feature",
  "geometry": {
      "type":"Polygon",
      "coordinates":[
        [[1.0,1.0],
          [8.0,1.0],
          [8.0,8.0],
          [1.0,8.0],
          [1.0,1.0]]
      ]
  }
}
```

SQL Example (FeatureCollection GeoJSON):

Output:

```json
{
  "type":"FeatureCollection",
  "features": [{
      "type":"Feature",
      "geometry": {
          "type":"Polygon",
          "coordinates":[
            [[1.0,1.0],
              [8.0,1.0],
              [8.0,8.0],
              [1.0,8.0],
              [1.0,1.0]]
          ]
      }
    }
  ]
}
```