> For the complete documentation index, see [llms.txt](https://docs.carto.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.carto.com/data-and-analysis/analytics-toolbox-for-bigquery/sql-reference/accessors.md).

# accessors

This module contains functions that provide information about internal geometries.

## ST\_ENVELOPE <a href="#st_envelope" id="st_envelope"></a>

```sql
ST_ENVELOPE(geog)
```

**Description**

Takes any number of features and returns a rectangular Polygon that encompasses all vertices.

**Input parameters**

* `geog`: `ARRAY<GEOGRAPHY>` input features.

**Return type**

`GEOGRAPHY`

**Example**

{% tabs %}
{% tab title="carto-un" %}

```sql
SELECT `carto-un`.carto.ST_ENVELOPE([ST_GEOGPOINT(-75.833, 39.284), ST_GEOGPOINT(-75.6, 39.984), ST_GEOGPOINT(-75.221, 39.125)]);
-- POLYGON((-75.833 39.125, -75.68 39.125 ...
```

{% endtab %}

{% tab title="carto-un-eu" %}

```sql
SELECT `carto-un-eu`.carto.ST_ENVELOPE([ST_GEOGPOINT(-75.833, 39.284), ST_GEOGPOINT(-75.6, 39.984), ST_GEOGPOINT(-75.221, 39.125)]);
-- POLYGON((-75.833 39.125, -75.68 39.125 ...
```

{% endtab %}

{% tab title="manual" %}

```sql
SELECT carto.ST_ENVELOPE([ST_GEOGPOINT(-75.833, 39.284), ST_GEOGPOINT(-75.6, 39.984), ST_GEOGPOINT(-75.221, 39.125)]);
-- POLYGON((-75.833 39.125, -75.68 39.125 ...
```

{% endtab %}
{% endtabs %}

<img src="/files/4m1BK9j4Wq34gat4HHd2" alt="EU flag" data-size="line">This project has received funding from the [European Union’s Horizon 2020](https://ec.europa.eu/programmes/horizon2020/en) research and innovation programme under grant agreement No 960401.


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