Hibernate version: 3.2.1

Is there a way apart from native SQL to persist partial object (i.e. just updating the fields with values in the object and not affecting other fields with null values)

for eg:
I have personInfo with below fields
username
password
firstname
lastname
age
sex...so on

I want to update only 2-3 fields of this table. So can i use saveOrUpdate passing the partially populated personInfo object leaving all the other properties null?

Or the only option is native SQL?

Thanks in advance,
Naresh