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VIQUEN: A Visual Query Engine for RDF

Tutorial 1: Extracting information from the Foundational Model of Anatomy (FMA)

In this tutorial, you will work through constructing a simple query which will extract information from the Foundational Model of Anatomy (FMA) ontology. You will also execute the query as well as visualize as explore the extracted information as a graph.

Step 1 - Starting the application

Start up VIQUEN from the directory in which you installed the application. You will see the query-building environment with an empty workspace.

Step 2 - Opening a saved file

We will now open the query workspace for this tutorial.
At the top of the screen, click on the "File" menu and choose "Open File". Alternatively, click on the "Open" toolbar icon . Navigate to the main VIQUEN directory and select the "tutorial1.mxe" file. Click on it and then click "Open file".
You should now see the following query workspace.

This simple query has 4 operations and consists of a single query block. The "Start" operation indicates the point from which the query will be compiled. Following this, the "Input" operation contains the input data sources for the query. The "Extract Tree" operation then specifies the information that we wish to extract from these input data sources, and the "Output" operation identifies the output graph of this query block. Each of these operations is connected to the next by a directed edge. These edges indicate the next operation in the query-building sequence.

We will now examine each of these operations in a little more detail.

Step 3 - The "Start" node: moving, collapsing and expanding nodes

Click on the "Start" node. The edges of the node will become highlighted to indicate that the node is selected.
Click and drag the "Start" node. This will move the node in the workspace. Note that the edge connected to the "Start" node is automatically updated when the node is moved.
Click on the minimize button (-). This will collapse the node.
Click on the maximize button (+). This will expand the node to its original size.
It is a good idea to keep nodes collapsed when you are not working on them since this will prevent accidental modification of the query parameters.

Now try moving, collapsing and expanding the other nodes in the workspace.

Step 4 - The "Input" node: choosing input data sources

Click on the "Select data sources" button. This will open the following window.

Step 5 - The "Extract Tree" node: specifying information to extract

Step 6 - The "Output" node: identifying the output graph

Step 7 - Executing the query

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