unhex function
Applies to: 
Databricks SQL Databricks Runtime
Converts hexadecimal expr to BINARY.
Syntax
unhex(expr)
Arguments
expr: A STRING expression of hexadecimal characters.
Returns
The result is BINARY.
If the length of expr is odd, the first character is discarded and the result is padded with a null byte.
If expr contains non hex characters the result is NULL.
Examples
SQL
> SELECT decode(unhex('537061726B2053514C'), 'UTF-8');
Spark SQL