Thank you for clarifying different issues for me. I'm sorry, just feeling so confused!
I changed the PK as you recommended
Component System.cfc
/*Primary Key*/
property name="SystemID" column="SystemID" type="string" ormtype="string" fieldtype="id" generator="guid";
/*Foreign Keys*/
/*property name="RegistrationNumber" fieldtype="one-to-one" cfc="Registration" fkcolumn="RegistrationNumber" hint="Constraint is Null";*/
Component Registration.cfc
/*Primary Key*/
property name="RegistrationID" column="RegistrationID" type="string" ormtype="string" fieldtype="id" generator="guid";
property name="System" fieldtype="one-to-one" cfc="System" mappedby="RegistrationNumber"
So, then when saving a new entry:
var system = populateModel(systemService.get(id )); //should return record, if id="" then generate a new id
var registration = populateModel(registrationService.get(registrationNumber));
system.setRegistrationNumber(ditprdon);
systemService.save( system );
Upon save, I still get "hibernate not able to convert string to uniqueidentifier".
I turned on the SQL Log, but the log doesn't show the actual values, just prepared sql statement... Does ORM/Hibernate expects the columns in the Entity to be in the exact order as the database table?