Support for rr:predicateMap?

[jensscheerlinck]

When trying to use a rr:predicateMap with a rr:column or rr:template value, the parsers produces no results.

Example:

rr:predicateObjectMap [
        rr:predicateMap [ rr:column 'TestColumn' ];
        rr:objectMap [
            rr:parentTriplesMap map:RechtsbronDocument; 
            rr:joinCondition [
                rr:child 'ChildColumn';
                rr:parent 'ParentColumn';
            ]
        ]
    ].

I only get the desired triples when using rr:predicateMap [ rr:constant ex:test ] or rr:predicate ex:test

[nkons]

Hi,

Thanks for reporting this.

In a rr:predicateMap, only an rr:constant is implemented. rr:column and rr:template are not implemented. To implement these would mean parsing them inside the loop in [1], in which only rr:constant is currently parser. A possible workaround would be creating one rr:predicateObjectMap per value in the TestColumn. Since these values are meant to be properties, I would assume their number is manageable?

1. https://github.com/nkons/r2rml-parser/blob/master/src/main/java/gr/seab/r2rml/beans/Parser.java#L290

[jensscheerlinck]

Hi,

Thanks for the response.

Unfortunately we have some 30 different values in the 'TestColumn'. Currently we have indeed split these up into 30 different maps. Which has a big impact on performance.

Creating different rr:predicateObjectMap elements would also be a possibility. However, we also tried this out before and the result was a very sparse matrix that made overall performance even worse.

[mmopitz]

Hi there. I was just wondering if you plan to support this feature in the near future? I'm currently running with the workaround mentioned above, but it would greatly simplify my mapping file if I could just use rr:templates in predicate position ;-)