I have the follwoing sequence defined in oracle:
CREATE SEQUENCE MySequence
MINVALUE 65536
MAXVALUE 4294967296
START WITH 65536
INCREMENT BY 1
CYCLE
NOCACHE
ORDER;
I wonder how can I access this via Hibernate (the next value each time i request) ? (via JDBC i have used getGEnerateKeys)
I need the id before I use it on another entity that needs to be persisted.
Thanks
For Oracle you should use GenerationType.SEQUENCE
@Id
@GeneratedValue(generator="MySequence", strategy=GenerationType.SEQUENCE)
@SequenceGenerator(allocationSize=1, name="MySequence", sequenceName="MySequence")
Edit: sequencename updated
Edit: refer to your comment: Your requirement sounds like composit/embedded id (using multiple columns as primary key) using sequence. but unfortunately both solution doesnt support sequence generator. So far I can say;
*You can create a native query via hibernate and append to index number using 'select mySequence.nextval from dual.
*Or you can create an oracle view for that with the new column which is showing sequence + index via subquery.
*This one very experimental and I didnt try but you can use @formula annotation. Example here.
I think that as long as the sequence is your primary key - for example
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private int id;
Then when you run:
Integer id = (Integer)session.save(obj);
It will return the id.
See the Javadoc: http://docs.jboss.org/hibernate/orm/3.5/api/org/hibernate/Session.html#save(java.lang.Object)
There's no JPA-standard way to do that, but you can certainly get access to the underlying JDBC connection, if you really need to. But note that, once the entity is persisted, the ID for the entity should be populated automatically.
