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\$1NumInteriorRings
<a name="ST_NumInteriorRings-function"></a>

ST\$1NumInteriorRings returns the number of rings in an input polygon geometry. 

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

```
ST_NumInteriorRings(geom)
```

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

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

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

`INTEGER`

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

If *geom* is not a polygon, then null is returned. 

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

The following SQL returns the number of interior rings in the input polygon. 

```
SELECT ST_NumInteriorRings(ST_GeomFromText('POLYGON((0 0,100 0,100 100,0 100,0 0),(1 1,1 5,5 1,1 1),(7 7,7 8,8 7,7 7))'));
```

```
 st_numinteriorrings
-------------
 2
```