Maybe a better question would be why can’t you version data in TDB? There is nothing stopping you storing different versions of the same data in different named graphs in a TDB store according to whatever naming scheme you desire.
To answer your original question the primary advantage is as you point out to do with size, if the data is tiny then the overhead of reading it from flat files every time it is needed is likely acceptable. However if the data is large it will start to become a bottleneck in the system, with TDB you pay the cost only once because TDB has minimal up-front costs to access a data (it’s just some memory allocations). Also when you come to actually manipulate data you may get substantial performance benefits with TDB since it has much more advanced indexing and data representation that an in-memory model as you’d typically get from reading a file from disk has. Rob On 01/04/2014 17:50, "David Jordan" <[email protected]> wrote: >A question has come up in my organization concerning the storage/access >of RDF/OWL using flat files versus TDB. There is interest in supporting >versioning of the ontologies which can be done at file system level. I >would assume as the size of the RDF increases (number of triples), it >becomes faster to use TDB. I also assume it is much easier to leverage >the indexing of TDB versus what would need to be done using flat files, >though for some of our application needs, the organizational structure of >the file system seems well suited. > >I am interested in hearing if anyone has any direct experience comparing >these two alternatives and whether there are any good rules of thumb >about when one approach becomes better than the other. Personally, except >for the versioning benefit of storing RDF/OWL in separate files in the >file system, I would think that in most cases TDB would be a better >choice, but I’d like to hear what others have to say about it. > >David Jordan >Senior Software Developer >SAS Institute Inc. >Health & Life Sciences, Research & Development >Bldg R ▪ Office 4467 >600 Research Drive ▪ Cary, NC 27513 >Tel: 919 531 1233 ▪ [email protected]<mailto:[email protected]> >www.sas.com<http://www.sas.com/> >SAS® … THE POWER TO KNOW® >
