Extension:Semantic OLAP

**MediaWiki extensions manual**
Semantic OLAP; Release status: unmaintained
Implementation	Ajax, Special page, Data extraction
Description	Analyse data in Semantic MediaWiki by using OLAP functionality
Author(s)	Tobias Wellertalk
Latest version	1.0 (2017-06-12)
MediaWiki	1.19+
PHP	5.3+
Database changes	No
License	MIT License
Download	GitHub: project page; git repository URL [help]; commit history; ; Note:; No localisation updates are; provided by translatewiki.net.

Semantic OLAP is an extension to Semantic MediaWiki that allows to query and analyse data, stored in the semantic MediaWiki, by using OLAP functionality. Users can analyse the data from different views by changing the pivot table. Semantic OLAP uses orbjs, which is based on React.js, to customize and control the pivot table.

Installation

The Semantic MediaWiki extension must be installed in order to use this extension.

Download, extract and place the file(s) in a directory called SemanticOLAP in your extensions/ folder.
Add the following code at the bottom of your LocalSettings.php file:
```
wfLoadExtension( 'SemanticOLAP' );
```
Done – Navigate to Special:Version on your wiki to verify that the extension is successfully installed.

Usage

Select Data

In the initial screen of the Semantic OLAP Special Page, the data that should be queried must be selected.

At least one Category and one Property must be selected.
Autocomplete simplifies the input and suggests available Categories and Properties

On the basis of the input, a simple ASK Query is created in the background. If no result is returned, a Popup appears with the corresponding ASK query.

Analyse Data

Tool allows to analyse the data by using OLAP functionality.

Use Drag&Drop to change the view on the pivot table
If multiple values are linked to the same Property then only the first Value is selected.
If a property is of type "Quantity", the corresponding unit is displayed.
Click on "Select Data" to get back to the initial screen and select the data for analysis

Filter and Sort Values

Semantic OLAP allows to filter for values. In order to filter, click on the right icon on the corresponding property and filter vor values either by

Matches (i.e. greater than, lower than)
Tick the concrete values

Export Data

The current view on the data is downloaded in spreadsheet format by clicking on the export xls button.

Future Work

Select aggregation function (sum, avg, max, min)
- Currently, only sum is available
Advanced ASK Queries/Selection of data
- Using advanced queries in SMW 2.5
- Compound Queries
Allow to display information in graphs

Ideas

- Include the Semantic OLAP into a page

Semantic OLAP Release status: unmaintained

Implementation	Ajax, Special page , Data extraction
Description	Analyse data in Semantic MediaWiki by using OLAP functionality
Author(s)	Tobias Weller^talk
Latest version	1.0 (2017-06-12)
MediaWiki	1.19+
PHP	5.3+
Database changes	No
License	MIT License
Download	GitHub: project page git repository URL ^{[help ]} commit history Note: No localisation updates are provided by translatewiki.net .