Re: SPARQL Query Results XML Format

Have you considered having more meta-data in the head element, e.g. to 
record the query (or ref to query), plus dataset (or ref to dataset) 
queried). Otherwise there doesn't seem to be any information identifying 
where the result bindings came from?

The motivation for this comes from work we're doing. In that work we do 
graph matching over a dataset, which (although currently stored in a 
relational database)  is a set of triples, such as (memberOfGroup 
Person1 Group1). We'd like to be able to store the query results for 
later retrieval and want to have provenance of the results, for several 
reasons

1) To know which graph matching application made the match, so we can 
compare results between different pattern matchers
2) To know which dataset we matched against, so that if the dataset 
changes then we'd be able to understand why results might differ 
(ideally we'd want provenance not jyust at the high-level name/id of 
dataset, but at the individual data triple level too).
3) To know what pattern matching parameters were set. These include 
obvious things like max number of results to return, or a time point/no 
of cpu cycles to expend on the query. This also includes, for inexaxt or 
approximate graph pattern matchers things like maximum cost, which are 
used if you have something like an ontological edit distance matching 
algorithm.
4) Results from one application might be used as (port of) a query to 
another application. This could occur if you had a serial workflow, when 
each application had a specialised capability (e.g. group finding), 
whereas the next application was an event matcher (with temporal 
constraint checking). Alternatively you might have a parallel workflow, 
where you divide the problem in parts (sub-graphs) , task to separate 
applications, and then merge the results all back together.

Thanks

Ian

-- 
Ian Harrison                Email: harrison@ai.sri.com
SRI International           Phone: 917 535 3976
380 Degraw Street           
Brooklyn, NY 11231          WWW: http://www.ai.sri.com/~harrison

Received on Tuesday, 14 June 2005 16:28:40 UTC