Sample Scenario

This page illustrates the usage of Explorator.

This scenario is also described in a short video (opens external site in separate window):

Video thumbnail. Click to play.

The repository contains geo-political data about countries in the World.

Suppose the user needs to find all the lakes contained exclusively in Russia (and not in any other country). One possible way to achieve this task is as follows:

  1. Find all the lakes in the database;
  1. Find Russia, the country;
  1. Find all the lakes in Russia obtaining a set which we will call LR;
  1. Find the countries that share a boundary with Russia (Russia’s neighbors);
  1. Find all the lakes in Russia’s neighbors, obtaining a set which we will call LN; and
  1. Build the set of the lakes contained exclusively in Russia by calculating the difference between the previous sets: LR-LN

First we must select the repository. Click on Menu and select Repositories. Deselect all, and select "Mondial". Click ok.

To find all the lakes in the database, a simple way is to search for “lake”:

Locate the Lake class in the resulting set, and get the set of instances of the Lake class by clicking on the Instances link, to obtain all the lakes in the database:

Next, to find Russia, search for “Russia” and locates the resource Russia in the resulting set:

To make sure it is the right resource, look at the resource details by double-clicking on it:

Next, to find all the lakes LR in Russia, select the set of all lake (clicking on the box) and set it as the subject of an SPO query by clicking on the [S] toolbar button:

Continuing to build the query, select the resource Russia and set it as the object of the SPO query by clicking on the [o] toolbar button:

Execute the query (click on the [=] toolbar button) to obtain the set of all lakes in Russia:

Next, to find the countries that share a boundary with Russia, look at the details of the Russia resource and locate the neighbor property, thereby finding its neighboring countries:

To find all the lakes in Russia’s neighbors, select the set of Lakes in Russia and sets it as the subject of the next query:

Selects the set of Russia’s neighbors and set it as the object of his query:

Execute the query to find all lakes in Russia’s neighboring countries:

Finally, to build the set of the lakes contained exclusively in Russia, we need to calculate the difference between the set of lakes in Russia and the set of lakes in Russia’s neighbors. To do this, select the first set and the difference operator:

Finally, select the second set (containing the lakes in Russia’s neighbors) and execute the difference operation by clicking on the equal [=] toolbar button, thereby obtaining the desired result:

Attachments