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balteo (12) [Avatar] Offline
I have an interrogation about page 302 section 12.2.4:

            for (Item item : items) {
                assertTrue(item.getBids().size() > 0);
                // select * from BID where ITEM_ID in (
                //  select ID from ITEM
                // )

My question is about the specific subselect i.e.
select ID from ITEM

Is this not going to return the whole ITEM table IDs?

If that is indeed the case, is it really an optimization to do so?