On Tue, Oct 4, 2016 at 7:32 PM, Julian Reschke <julian.resc...@gmx.de> wrote: > At least in our DocumentStoreImplementations (Mongo and RDB), making the > UUID something indexed by the storage (so either Mongo or the relational > database) should be relatively cheap (after all, the UUID never changes once > assigned, right?).
Optimizing index storage is orthogonal to this discussion. Indexing unnecessary stuff has a cost irrespective of the fact where it is done. Further its not possible to directly leverage the DB/Mongo indexing for uuid. As uuid property is also versioned (in MVCC terms). So if a referenceable nodes gets created->deleted->created frequently you need to keep record of all those uuid. And this would lead to 1..n mapping between entry in db and uuid which cannot be handled easily via DB indexes. Chetan Mehrotra
