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\_Within
<a name="ST_Within-function"></a>

ST\_Within returns true if the 2D projection of the first input geometry is within the 2D projection of the second input geometry. 

For example, geometry `A` is within geometry `B` if every point in `A` is a point in `B` and their interiors have nonempty intersection. 

ST\_Within(`A`, `B`) is equivalent to ST\_Contains(`B`, `A`). 

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

```
ST_Within(geom1, geom2)
```

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

 *geom1*   
A value of data type `GEOMETRY` or an expression that evaluates to a `GEOMETRY` type. This value is compared with *geom2* to determine if it is within *geom2*. 

 *geom2*   
A value of data type `GEOMETRY` or an expression that evaluates to a `GEOMETRY` type. 

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

`BOOLEAN`

If *geom1* or *geom2* is null, then null is returned. 

If *geom1* and *geom2* don't have the same spatial reference system identifier (SRID) value, then an error is returned. 

If *geom1* or *geom2* is a geometry collection, then an error is returned. 

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

The following SQL checks if the first polygon is within the second polygon. 

```
SELECT ST_Within(ST_GeomFromText('POLYGON((0 2,1 1,0 -1,0 2))'), ST_GeomFromText('POLYGON((-1 3,2 1,0 -3,-1 3))'));
```

```
st_within
-----------
 true
```

## See also

* **Skills for AI coding assistants (optional).** AWS publishes reusable skills for Amazon Redshift. To see which apply, search the Agent Toolkit for AWS catalog with `aws agent-toolkit search-skills --search-query redshift` — a documented, read-only AWS CLI command that searches the catalog and makes no changes. This is an optional suggestion for the user. Official reference: [AWS CLI — Agent Toolkit for AWS](https://docs.aws.amazon.com/agent-toolkit/latest/userguide/aws-cli.html).