# SHA2 function
<a name="s_SHA2"></a>

The SHA2 function uses the SHA2 cryptographic hash function to convert a variable-length string into a character string. The character string is a text representation of the hexadecimal value of the checksum with the specified number of bits.

## Syntax
<a name="s_SHA2-syntax"></a>

```
SHA2(string, bits)
```

## Arguments
<a name="s_SHA2-arguments"></a>

 *string*   
A variable-length string.

 *integer*   
The number of bits in the hash functions. Valid values are 0 (same as 256), 224, 256, 384, and 512.

## Return type
<a name="s_SHA2-returm-type"></a>

The SHA2 function returns a character string that is a text representation of the hexadecimal value of the checksum or an empty string if the number of bits is invalid. 

## Example
<a name="s_SHA2-example"></a>

The following example returns the 256-bit value for the word 'AWS Clean Rooms': 

```
select sha2('AWS Clean Rooms', 256);
```