Help:SMWAddExtensions

This section gives some guidance on, and provides examples for using other Semantic Mediawiki (Semantic MW) extensions. Basic features of the Semantic MW and the Semantic Forms extension are explained separately (see the box on help sections above). All SemanticMW extensions described here require prior installation of the basic Semantic Mediawiki components.

Semantic Drilldown extension

For more detailed descriptions of this extension see the Semantic Drilldown website.

Introduction

Semantic Drilldown is very useful for browsing and filtering the semantic data entered into a wiki. As with other SemanticMW features, Semantic Drilldown is closely linked to the category system of a wiki and Semantic Drilldown can only work through a specific category. As an example we explain here the different steps for modifying the Category:Publications to enable specific filter options.

Defining filters

1. Create the page Filter:Journal by typing this name into the search box.
2. The filter page basically needs only a statement on which property the filter is based in the form "[[Covers property::Property:Publication journal]]". However, you might want to add also some explanationary text.
3. Create another filter for the property Publication year.

Adding filter definitions to a category

We now add these 2 filters to the page Category:Publications. For this we need statements like "[[Has filter::Filter:Journal]]".

Using Semantic Drilldown

Got to the "Semantic Drilldown" section of the Special:SpecialPages and select Browse data. In the top right of this page you find a box with the different categories of this wiki, sorted alphabetically. The first category on this list has been selected. Since most categories do not contain any filters, most "browse pages" do not look differently from the normal category pages. Select the category Publications. On the top of this page you can now click on different journals and publication years. The Drilldown system then filters out the category pages according to your selections. Of course, the Drilldown system is especially useful if many data have been entered into system.

Semantic Result Formats

The Semantic Result Formats extension adds several features for displaying query results with semantic data in different formats, e.g. a graphical format. For a detailed description of this extension see the Semantic Result Formats website.

The use of these features is very simple, just use the line "format=<format type>" together with the #ask function. The following examples demonstrate some of the format types:

• Displaying data in a graph (Google bar).
• Displaying sums or averages of a data set.
• Ordering data according to semantic properties.