Andy I recently put a comment on JENA-507 about this same issue
It would be nice to have some means to be able to inject custom aggregates without needing to modify the grammar with new tokens (because that appears to be the only way to add custom aggregates right now). It would be nice to have some sort of central registry of custom aggregates which the parsers could then simply consult and either output an aggregate if explicitly registered as such and otherwise use the existing behaviour of assuming a custom function Rob On 17/10/2014 15:44, "Joshua TAYLOR" <[email protected]> wrote: >On Thu, Oct 16, 2014 at 10:39 PM, Ian Emmons <[email protected]> wrote: >> the example he gave is an aggregate that would compute the maximum >>score of a grouping of hotels based on multiple properties of the hotels. > > >Things like that are already possible, though. You can do, e.g., > >select ?hotel (max( (?price+?size)/?distance ) as ?ranking ) where { > ?hotel :price ?price ; :size ?size ; :distance ?distance . >} >group by ?hotel > >You can do a lot just with SPARQL 1.1., and if you add some custom >(non-aggregate) functions in there, you can do even more. Without >specifics, it's hard to say, but I wouldn't be entirely surprised if >the actual use case is already possible. > >//JT > >-- >Joshua Taylor, http://www.cs.rpi.edu/~tayloj/
