I think I would like to see a method on the Dataset that returns the union model (e.g. dataset.getUnionModel(). It seems like this would be a trivial implementation for TDB and that code exists for the in memory versions.
It would mean that other packages that implement Dataset would have the opportunity to make more efficient calls like TDB would do. Do you suppose we can do this in 2.12.1 ? Claude On Sun, Jun 29, 2014 at 11:32 AM, Andy Seaborne <[email protected]> wrote: > On 29/06/14 10:54, Claude Warren wrote: > >> Is there a way to get a model that is the union of all the models in the >> dataset that works across all implementations of Dataset? >> >> > Hi Claude, > > GraphUnionRead should do it. Being very general, it is not as efficient > (it has to do a 'distinct' on each graph.find which either is a not big > deal for small graphs and a significant amount of memory on large graphs > close to the limits). > > For datasets, there are two ways: > > 1/ DatasetGraphViewGraphs > > which should do it. I haven't pushed it more visibly because it may be > better to make changes to the DatasetGraph hierarchy (Jena3 - or at least a > significant bump to 2.X). > > > 2/ DynamicDatasets > (older code - actually designed for a slightly different usage but > happenes to handle this case) > > Both relatively untested. > > With all of these, if you use it over TDB, it will not use TDB's internal > handling of union graphs which is much better. > > 3/ Invert the problem - use TDB-in-memory! > > Andy > > > > -- I like: Like Like - The likeliest place on the web <http://like-like.xenei.com> LinkedIn: http://www.linkedin.com/in/claudewarren
