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\$1DWithin
<a name="ST_DWithin-function"></a>

ST\$1DWithin returns true if the Euclidean distance between the 2D projections of the two input geometry values is not larger than a threshold value. 

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

```
ST_DWithin(geom1, geom2, threshold)
```

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

 *geom1*   
A value of data type `GEOMETRY` or an expression that evaluates to a `GEOMETRY` type. 

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

 *threshold*   
A value of data type `DOUBLE PRECISION`. This value is in the units of the input arguments. 

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

`BOOLEAN`

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

If *threshold* is negative, then an error is returned. 

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

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

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

The following SQL checks if the distance between two polygons is within five units. 

```
SELECT ST_DWithin(ST_GeomFromText('POLYGON((0 2,1 1,0 -1,0 2))'), ST_GeomFromText('POLYGON((-1 3,2 1,0 -3,-1 3))'),5);
```

```
st_dwithin
-----------
 true
```