Expressions passed to this function must have a data type of VARCHAR(n) CHARACTER SET UNICODE, where the maximum supported size (n) is 32000. You can also pass arguments with data types that can be converted to VARCHAR(32000) CHARACTER SET UNICODE using the implicit data type conversion rules that apply to UDFs. For example, CAMSET(CHAR) is allowed because it can be implicitly converted to CAMSET(VARCHAR).
The input to this function must be Unicode character data.
If you specify NULL as input, the function returns NULL.