Is it possible to get an iterator for a query created
using the criteria API ?

I want to use the criteria API to process large result sets

No, it is not yet possible. Don't expect this before Hibernate 2.2.

Has this been added? I have a requirement to export massive amounts of data as a CSV, and am already using the Criteria API. It would be swell if I could stream the results out using an iterator, rather than having to wait until a whole list is 100% populated. Thanks!
--Corey

yes

criteria.scroll(ScrollMode.FORWARD_ONLY)

steppinrazor: While .list().iterator does get me an iterator, it forces Hibernate to fully load the backing list before I can iterate through the first one. This is fine for small datasets, but for large ones (say, millions of rows), this could really be a drain on system memory.

ferozz: This is exactly what I was looking for. I guess I missed it since I was looking for a method called "iterate", not "scroll".

Thanks for both of your help!
--Corey

Hibernate does load the entire result set before you get the iterator. In addition to Ferozz's input you can also get an iterator like this:



This however only returns the ids and not the entire object until you iterate, then a select is generated to retrieve all the columns. In certain circumstances this can be a good optimization (as usually optimization is associated with minimal row return).

Could you and Ferozz look at something that I posted that no one has replied to and let me know what you guys think http://forum.hibernate.org/viewtopic.php?t=986008