The problem is that explicit query allows orderings, while indirect (via Artist.getPaintings()) does not (the same can be said about e.g. prefetches though). So, if I want some array to be sorted (which is quite often) I have to create queries for to-many orderings. Since I often use reflection-based invocations, I have to create new methods, like getOrderedPaintings(), moreover, bother about caching the data. IMO the feature is easy to implement (most is in the patch, actually) and worth it. Also note that we've seen several same wishes on the user list
artist.getPaintings(Comparator/Ordering) is fine, but we can't generate that methods for every relationship, and more generic methods will lose things like Java Generics advantages. My vision is that this feature will be used for relationships that are ordered is same way [by default] in every context - e.g. I want people to be sorted by name everywhere. 2010/3/4 Aristedes Maniatis <[email protected]> > On 4/03/10 8:28 AM, Andrus Adamchik wrote: > >> Also here is a reason why I don't find ordering of relationships >> particularly useful is that things like ordering are context dependent >> ("context" in a general sense)... The same mapping can be used by >> different UI frontends with different ordering requirements. >> > > Having a default ordering for ObjEntities defined in the model is what > Rails does. Any time you fetch that entity, be it directly through a Query > or via a relation, you get the results back with that ordering. > > Personally I don't see the point. Ordering in the database is very useful > if you are paging the results. Or using a limit. But when following > relations, neither of those things applies, so you may as well just do it in > memory once you have the list returned. > > Perhaps a simplified notation might be useful though: > > artist.getPaintings(Comparator/Ordering) > > > > Ari > > -- > --------------------------> > Aristedes Maniatis > GPG fingerprint CBFB 84B4 738D 4E87 5E5C 5EFA EF6A 7D2E 3E49 102A > -- Andrey
