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/). 

# IS\_VARCHAR function
<a name="r_is_varchar"></a>

Checks whether a variable is a `VARCHAR`. The IS\_VARCHAR function returns `true` for all strings. The function returns `false` for any other values.

The IS\_VARCHAR function is a superset of the IS\_CHAR function.

## Syntax
<a name="r_is_varchar-synopsis"></a>

```
IS_VARCHAR(super_expression)
```

## Arguments
<a name="r_is_varchar-arguments"></a>

*super\_expression*  
A `SUPER` expression or column.

## Return type
<a name="r_is_varchar-returns"></a>

`BOOLEAN`

## Examples
<a name="r_is_varchar_example"></a>

To check if `abc` is a `VARCHAR` using the IS\_VARCHAR function, use the following example.

```
CREATE TABLE t(s SUPER);

INSERT INTO t VALUES ('abc');

SELECT s, IS_VARCHAR(s) FROM t;

+-------+------------+
|   s   | is_varchar |
+-------+------------+
| "abc" | true       |
+-------+------------+
```