Hi Rurik Thanks for your reply. The number of triples is what is a concern to me also. Do you remember if this was a matter of entity size (verboseness of RDF), or query efficiency?
I too am leaning towards using a timeseries data to mix in results using an API at query-level, but lack a decent platform or database to experiment with. - Ashley On 28 January 2015 at 15:31, Rurik Thomas Greenall <[email protected] > wrote: > Hi Ashley, > > I worked for a large Norwegian oil company on sensor readings in relation > to time-series data from data historians. > > For numerous reasons (including the sheer number of triples), we planned to > move away from the idea of storing the data directly as RDF, but rather > mapped data from the historians to RDF on-the-fly, providing a simple REST > interface to serve the RDF. The PoC for this included data about the > sensors and the measurements taken as well as links to previous/subsequent > measurements. > > I played with the idea of requesting period series via the interface as > well as single instants. > > The PoC worked well enough to be used in a real-time 3D visualisation of > the subsea template, but I'm not sure how this ended up as I ended my > contract before the project was completed. > > Regards, > > Rurik > > On Wed, Jan 28, 2015 at 11:02 AM, Ashley Davison-White <[email protected]> > wrote: > > > Hi all > > > > I'm currently looking at the feasibility of storing time series data in > > jena (TDB); specifically energy data. In fact, right now I'm looking for > a > > reason not to!- so far, my research has shown me it is possible but > there > > seems to be a lack of experimentation in doing so. > > > > I'm wondering if anyone is aware of previous research or projects? And if > > there are any potential advantages/disadvantages? > > > > From my limited experience, in-place updates are not possible, so > storing a > > rollup of data (i.e. an entity of readings per day, rather than per > minute) > > is not possible; so each reading would need to be it's own tuple. With a > > large data set, I can see this being a problem - especially with the > > increased verboseness of triple data vs a traditional time series > database. > > However, for small scale, I don't see this as a problem. > > > > I'm interested to hear opinions on the topic. > > > > Regards, > > - Ashley > > >
