W3C R2RML Compliance - ConstantB/ontop-spatial GitHub Wiki

This page describes the state of the W3C R2RML Compliance tests executed with ontop system.

Currently we are able to execute all the tests, except the ones presented below.

• D009 Generation of triples from foreign key relations

Reason. This test produces joint mapping SQL query and the variables in the ontop mapping axiom need to be renamed.

• D009 Generation of triples to multiple graphs

Reason. Multiple graphs are not supported.

• D010 Template with table columns with special chars and backslashes

Reason. Template uses special characters, which are reserved in ontop for placeholders (such as {} ).

• D011 M to M relation, by using a SQL query

Reason. The alias used in the SQL query is the same as the column names in other two tables. Therefore some entries in the lookup table get overwritten.

• D014 Triplesmaps with rr:inverseExpression, rr:joinCondition, and referencing object maps

Reason. rr:inverseExpression and BNode in ontop mapping are currently not supported.

• D014 Three tables, one primary key, one foreign key

Reason. The SQL query contains unparsable (at the moment) elements, therefore, ontop cannot extract variable names needed for the mapping construction.

• D014 Triplesmaps with rr:inverseExpression and rr:joinCondition

Reason. rr:inverseExpression not supported. Duplicate column names in the produced SQL query.