VGR (Visual Graph Requestor)

A simple way for SPARQL requests

The Basic Idea
Layouts
VGR interface concepts
Graph Exploration
How to define forms

The Basic Idea

RDF is really powerful and wonderful for ontology modeling and knowledge acquisition. But, after the building and validation of some ontology, the exploitation could start. People involved in exploitation are expert in their domain, not in the arcane of RDF.

Just think about traditional relational database exploitation: people using entry forms don't know SQL and even less the queries and join optimization. They need entry forms and agree with that.

VGR is a tentative to make RDF graph exploration based on an RDFS ontology as simple as possible.

The user can request a RDF store with forms (similar to classical SQL/MS Access forms) without any SPARQL knowledge.
The user can navigate through the graph returned by the request guided by his imperious information needs....
These forms are build by a knowledge engineer who knows SPARQL.
Each form is based on SPARQL (with a little modification: each $variable will automatically generate a request form field).

Layouts (screen shoots)

Each request could be viewed (and explored see more in request exploration) in different layouts :

as the classical energy layout

or as the force directed (also classical) layout

but also in orthogonal layout. The more expressive layout
only available for small or middle sized graphs (CPU expensive).

Forest layout (useful for taxonomy but could be applied for all graphs)

Circular layout (also classical but not so useful).

3D layout (the power of OpenGL.....)

VGR interface concepts

The different components of the interface are :

the catalog panel (1) (similar to file tree in a Windows explorer). It is organized in :
- a catalog of all graphs available in the RDFstore,
- a catalog of SPARQL forms.
- a catalog of requests
- a catalog of layout styles.
- a catalog of all the Datalog rules set available in the RDFstore (StrixDB RDFstore specificity).
Tabbed views (2) of graphs layout.
a floating minimap (3) to navigate inside the graph layout (2).
A ribbon bar in the look-and feel of Microsoft Office (4). Three bars are available :
- Home bar to change the layout and offers common actions;
- Exploration bar to navigate and explore the graph ;
- Style Bar to change colors, line styles, etc... of the layout.
the request panel (5) used to edit SPARQL requests and instanciate SPARQL templates.

GRAPH and request exploration

How to define forms

Defining forms is straight forward for anyone who knows SPARQL. For example the following request :

with text labels defined with the following interface :