[jboss-dev-forums] [Design of JBoss Portal] - Re: Hibernate Query.iterate()

[the-gtm]

I checked Hibernate's doc :
http://www.hibernate.org/hib_docs/v3/reference/en/html/objectstate.html#objectstate-querying-executing-iterate

Basically Query.list() will do one query, Query.iterate() will do n+1 queries except if entities whose identifier are returned are already cached. In Query.list() and Query.iterate(), you get lazily loaded proxies, meaning Hibernate has the data (from the initial query) but the object's fields are not filled yet. This is just a reflection optimisation, not a querying one.
Obviously there's a performance tradeoff here : you're trading queries number vs result set size. IMO the overhead cost of each query is so high that you'd rather go with a single query.

Anymay, in the forum module most of the methods using Query.iterate() are returning a list. A better solution is as simple as 

return query.list();

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