Hi, On Thu, Apr 26, 2012 at 4:52 PM, Emmanuel Lécharny <[email protected]> wrote: > Hi guys, > > currently, we can replace an existing value when its associated key exists > in the BTree. What I'd like to do is to replace both key and value in this > case. > > The rational is that the key mau contain some extra information that are not > used to find the key, like the nbChildren/nbDescendant for a ParentIdAndrdn > key in the RdnIndex. > > Is there an easy way to do that with JDBM, or should we extend the API it > offers ?
as I understand you are trying to store some auxiliary information per key? With JDBM we can: - provide <K, aux> tuple as the key and pass the key comparator to be the comparator for the actual keys. - change JDBM code to update key inside when replacing an entry. however, in general, I do not think we can expect a key/value store to update the key when replacing an entry. So I am not sure it is a good idea to do this kind of thing. > > That would save us a lot of CPU, as we currently have to drop the key and > values and reinject them, which is an costly operation... > > Ideas ? > > -- > Regards, > Cordialement, > Emmanuel Lécharny > www.iktek.com > thanks Selcuk
