Mapping Schema Format

This page describes the mapping schema format used to save interlinkings using the SPARQLing Unicorn QGIS plugin.

A mapping schema is defined in XML and saves mappings from QGIS vector layer columns to relation URIs in the to-be-build RDF graph and makes them reusable.

Consider the following example:

Example:

<?xml version="1.0"?>
<data>
    <file class="http://onto.squirrel.link/ontology#RomanRoad" indid="groupID" indidprefix="line_"
    namespace="http://lod.squirrel.link/data/intinerarium-antonini/"
    attnamespace="http://lod.squirrel.link/data/intinerarium-antonini/" epsg="4326" nometadata="true" attachepsg="true">

    <column name="groupID" prop="data" propiri="http://onto.squirrel.link/ontology#groupID" range="http://www.w3.org/2001/XMLSchema#string"/>

    <addcolumn prop="annotation" propiri="http://www.w3.org/2000/01/rdf-schema#label" value="Intinerarium Antonini Line"/>

    </file>
</data>

This mapping schema defines a mapping for a RomanRoad dataset, a dataset of annotated LineStrings. The mapping schema defines a target namespace (namespace) for the instance, an attributenamespace (attnamespace) for relations and coordinate reference system (epsg) and possibly a column which may be used as the individual id (indid).

Then, each column is assigned a configuration with the following attributes:

• name: the name of the column in the QGIS vector layer
• prop: The property type to convert into (DataProperty (data), ObjectProperty (obj), AnnotationProperty (anno), SubClass (subclass))
• propiri: The IRI used in the graph to represent the respective column
• range: The range of the property