Semantic MediaWiki

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Category:MediaWiki extension
Semantic MediaWiki
Extension name Semantic MediaWiki
About this article / disclaimer
Logo SMW Logo.SVG
Screenshot [[Image:|135px]]
Location of the main author Oxford, England
Coordinates of the main authors 51.752022222222, -1.257725
Developers Markus Krötzsch, Denny Vrandecic, Jeroen De Dauw, others
Licences
Description Semantic MediaWiki is an extension for managing structured data in your wiki and for querying that data to create dynamic representations: tables, timelines, maps, lists, etc.
Mediawiki requirements Any recent version.

However, we suggest using MW 1.22 (dec 2013). This version includes support for Composer, a dependency manager that will ease installation.

Dependencies Validator, ParamProcessor
Related extensions (documented here) Semantic Drilldown, Semantic Forms, Semantic Forms Inputs, Semantic Maps, Semantic Result Formats
Related extensions
Discussion
Language support Many
Status stable
First release date 2005/01/01
Last release date (as of 2014/05/02!) 2014/04/28
Last version number 1.9.2 (40ea19e)
Programming language PHP
Alternatives
Website home page
Publications
Support websites web site
Example websites
Last edited 2014/05/02

Draft

1 Introduction

Semantic MediaWiki (SMW) is an extension of Mediawiki – the wiki application best known for powering Wikipedia – that helps to search, organise, tag, browse, evaluate, and share the wiki's content. While traditional wikis contain only text which computers can neither understand nor evaluate, SMW adds semantic annotations that allow a wiki to function as a collaborative database. Semantic MediaWiki was first released in 2005, and currently has over ten developers, and is in use on hundreds of sites. In addition, a large number of related extensions have been created that extend the ability to edit, display and browse through the data stored by SMW: the term "Semantic MediaWiki" is sometimes used to refer to this entire family of extensions. Semantic MediaWiki has been funded in part by projects of the Framework Programmes (FP) of the European Union, SEKT and ACTIVE and by project Halo.” (Introduction to Semantic MediaWiki, retrieved 14:31, 24 August 2011 (CEST))

According to Semantic MediaWiki, “is currently in active use in hundreds of sites, in many languages, around the world, including Fortune 500 companies, biomedical projects, government agencies and consumer directories”.

See also:

2 Semantic properties

2.1 Properties and semantic web triplets

At the core of Semantic MediaWiki are so-called properties. Properties can be understood as "categories of information" and they are encoded in a way that a machine can understand. If you use a property + value in a given page, you implicitly create a so-called triplet.

For example, if we would like to add the information that Semantic MediaWiki is related to Semantic Forms we get the following triplet:

Semantic MediaWiki - Is related to - Semantic Forms
(Subject)            (predicate)     (object)

In Semantic MediaWiki, we create triplets by adding code defining property/value pair to a page. Therefore, with respect to the above example:

  • This page (Semantic MediaWiki) is the subject that we describe with a property
  • Is related is the property name, i.e. the so-called predicate
  • The Semantic Forms page is the value of the property and represents the object

The corresponding wiki code looks likes this:

[[Is related to::Semantic Forms]]

Similarities with RDF

In the Resource Description Framework RDF, a fragment like the following defines the same relationship.

<swivt:Subject rdf:about="http://edutechwiki.unige.ch/en/Special:URIResolver/Semantic_MediaWiki">
  <property:Is_related_to rdf:resource="http://edutechwiki.unige.ch/en/Special:URIResolver/Semantic_Forms"/>
</swivt:Subject>

In some ways, Semantic MediaWiki is the Wiki equivalent of RDF. Semantic data of a page can be exported as RDF like this:

[http://edutechwiki.unige.ch/en/Special:ExportRDF/Semantic_MediaWiki RDF feed], e.g. click on RDF feed

2.2 Property types

Properties in a Semantic MediaWikis define typed data, in a similar way as in object-oriented programming. Properties are used with the [[property_name::property_value]] syntax. By default, the value of a property is a wiki page, i.e. default data type of a property is simply a wiki page.

MediaWiki [[is a:: Wiki]]

The following example shows a value that is an URL. However, this does not yet mean the data type of Has website is an URL. Since default values for properties are wiki pages, we must explicitly create and edit the property page as explained further down.

[[Has website:: http://www.semantic-mediawiki.org/wiki/Semantic_MediaWiki]]

The above code will be shown as http://www.semantic-mediawiki.org/wiki/Semantic_MediaWiki ,i.e. the reader will see a clickable URL. Let's now look at property types.

Data types for property types

There exist several property types, for example:

  • Page (a wiki page, this the value by default, i.e. if you don't define a data type, a property value will display as "blue" or "red" link to a normal wiki page)
  • String (a short text)
  • Text (a longer text)
  • Code (same but pre-formatted)
  • URL (various kinds of URIs, including http://)
  • Number
  • Date
  • Enumeration (lists of values, i.e. of all the other types)
  • Boolean

Manual coding

  • Each property is defined through a page in the properties namespace. To create a property with aproperty_name and a value, just use the following syntax in any other page:
[[property_name:: your_property_value]]
  • You then can type the property. By default a property is of type page, i.e. it will link to a normal wiki page. For example [[is a:: Wiki]] will declare that this is a Wiki and then link to the page Wiki like this: Wiki

To define a property and its type there are three methods

(1a) Create a property instance with a value, then create/hand code the property page

  • Create the property using [[property_name:: your_property_value]] or use templates as explained in the Semantic Forms article
  • Create or edit the property:your_property page and add a type declaration like this:
This is a property of type [[Has type::URL]].

(1b) Use the Create with Form

  • Same principle, but it will allow selecting a data type from a pull down list.

(2) Use Special:CreateProperty

The easiest way to create a property (including its page and the type declaration) is to use the form in Special:CreateProperty "special" page.

The following screenshot shows a property page for property that is being used in page, but that is not defined yet. Do define it, either use method 1a or 1b as explained just above.

..............

2.3 Displaying properties

(under construction ...)

The way a property will be displayed depends on its type and an additional parameter. By default, only the value will be shown, either as simple text or as a link.

Values that are not links

We defined a data type of property has accronym as string, therefore the value will not show as a wiki link (as per default data type): The following table shows what happens:

input output description
[[has acronym::SMW]] SMW Most typical use of properties
[[has acronym::SMW::TheFuture::]] SMW Defining two values (shortcut)
[[has acronym::SMW| ]] Value will not be shown
[[has acronym::SMW|MWS]] MWS An alternative text will be shown
[[:has acronym :: SMW]] has acronym :: SMW Creates a link instead of a property (useless)

2.4 Annotated values

The Swiss Grading scale goes from 0 to [[grading scale:=6]]
Gives: The Swiss Grading scale goes from 0 to 6

2.5 Finding properties

There are several options that could help finding properties.

Default tools
Extensions that help browsing / listing

3 Inline queries

Semantic Mediawiki includes a query language for semantic search. According to the manual (7/2013), it can be used in three contexts:

  1. Through the form of the Special:Ask page,
  2. in so-called concepts, i.e. saved queries,
  3. and in inline queries.

Most frequent use seem to be inline queries.

Queries usually define three things:

  1. Which page(s) to select. Read Selecting pages (semantic-mediawiki.org)
  2. What information to display about those pages. Read Displaying information (semantic-mediawiki.org)
  3. How the results should be formatted. Additional extensions like Semantic Result Formats add further possibilities.

Inline queries dynamically include query results as in the examples below. This functionality is implemented with so-called parser functions.

  • The #ask function takes a number of parameters, in particular: page selection, information to display, and how.
  • the #show function displays information for a single page, i.e. it's a kind of shortcut for the #ask function.

One simple query would list all pages in a category. The following code:

{{#ask: [[Category: MediaWiki extension]]}}

produces a simple line:

Maps (MediaWiki extension), Mediawiki collection extension installation, Page Forms, Semantic Drilldown, Semantic Forms Inputs, Semantic Maps, Semantic MediaWiki, Semantic Result Formats, VisualEditor

3.1 Simple queries

By definition, various query clauses are combined with an AND operator

The following code selects all pages in the category software information and that include a property value Yaron Koren for the property Is developed by.

{{#ask: [[Category: MediaWiki extension]] [[Is developed by::Yaron Koren]]
 | ?Has name
 | format=ul
}}

It will produce this:


We also can use wildcards, e.g. if we wanted to list all pages that do include a property "Is developed by", we would use the following expression:

{{#ask: [[Category: MediaWiki extension]] [[Is developed by::+]]
 | ?Has name
 | format=ul
}}

It will produce this:


3.2 Ask syntax

3.2.1 Overview

Roughly speaking, syntax of #ask: is the following: It it includes three groups of information:

  1. Ask for pages that satisfy some conditions
  2. Tell which information to show, e.g. property/values,
  3. Define how to render the results, e.g. display items as a table or graph, sort results, add labels and table headers etc. See Semantic Result Formats for a more detailed introduction.
{{#ask
search_clause_1
search_clause_2
......
| ?Information_1 to display
| ?Information_2 to display 
| ?......
| Result_format_parameter 1 = x
| Result_format_parameter 2 = y
|....
}}

By default, queries will return a list wiki pages (i.e. without telling which other information to show and whether the page itself should be skipped).

Search conditions (clauses) can include property/values (including wildcards and comparators), categories and some other stuff. In addition, you can use disjunctions (or's).

3.2.2 Searching within categories and pages

To search within a category and all subcategories, simply use the normal wiki syntax, e.g.

[[Category: MediaWiki extension]]

A query including just this condition would return all the pages in the MediaWiki extension'. For example, the query {{#ask: [[Category: MediaWiki extension]]}} produces this list: Maps (MediaWiki extension), Mediawiki collection extension installation, Page Forms, Semantic Drilldown, Semantic Forms Inputs, Semantic Maps, Semantic MediaWiki, Semantic Result Formats, VisualEditor

Notice: This makes me wonder what happens if you have circular category structures ...

3.2.3 Searching for property values

Property conditions can take several forms, i.e. define a value, use a wildcard, or include comparators

Simple property value search

To search for a property with a given value, use the normal property syntax, e.g.

[[Developed with::MediaWiki software]]

The query {{#ask: [[Developed with::MediaWiki software]]}} produces this list of pages: CS4CS, Transcribe Bentham

Wildcards

  • Use a + for wildcards

The query {{#ask: [[Supports languages::+]]}} produces this list of pages: Maps (MediaWiki extension), Mediawiki, Mediawiki collection extension installation, Page Forms, Semantic Drilldown, Semantic MediaWiki, Some software

See also the ~ (like) operator below for string comparison.

Comparators

Comparators work with property values and they are placed after the :: in property conditions.

>> and <<: "greater than" and "less than"
> and <: "greater than or equal" and "less than or equal"
However, if $smwStrictComparators] = true;, you get normal behavior, i.e. "greater than" and "less than"
and : "greater than or equal" and "less than or equal"
!: "not" ("unequal")
~: «like» comparison for strings.
In the comparison sting you can use "*" to match a chain of characters and "?" to match any single character
!~: «not like» comparison for strings

The query {{#ask: [[Was last edited::>1 September 2013]]}} produces this list of pages: Semantic MediaWiki, Semantic Result Formats, VisualEditor

The query {{#ask: [[Has field of science::~bio*]]}} produces this list of pages: Budburst, Notes from Nature, Plankton Portal, Worm Watch Lab, i.e. it will return pages whose Has field of science property includes at least one "bio". Below, a table that also lists the property values found

 Has field of science
Budburstbiology
Notes from Naturebiology
taxonomy
biological classification
Plankton Portalbiology
biological oceanography
planktology
climatology
Worm Watch Labbiology
genetics
medicine
neuroscience

Some comparisons can be hairy, e.g. values that are rounded for display, coordinates and such.

3.2.4 Subqueries

 <q> .... </q>

Examples:

3.3 Displaying results

Read the main article: Semantic Result Formats for more information about this topic, in particular if you are interested in visualizations made with JavaScript libraries.

By default, results that include more than one property to be shown are shown as a table. The following code selects the same pages as above, but also displays has last revision number values.

{{#ask: [[Category: MediaWiki extension]] [[Is developed by::Yaron Koren]]
 | ?Has name
 | ?has last revision number
 | ?Is developed by
}}

produces this:

 Has nameHas last revision numberIs developed by
Page FormsSemantic Forms2.6 (Dec 2013)Yaron Koren
Stephan Gambke
others
Semantic DrilldownSemantic Drilldown1.2.5 (June 2013)Yaron Koren
David Loomer
Semantic Forms InputsSemantic Forms Inputs0.7Stephan Gambke
Yaron Koren
Jeroen De Dauw
Sanyam Goyal
Yury Katkov
others
Semantic Result FormatsSemantic Result Formats1.9.1 alpha (9482833)Jeroen De Dauw
Frank Dengler
Steren Giannini
James Hong Kong
Fabian Howahl
Yaron Koren
Markus Krötzsch
David Loomer
Joel Natividad
Denny Vrandecic
Nathan Yergler
others

Semantic Result Formats allows to produce graphics. The following displays all pages where Yaron Koren is defined as developer plus the participations of other developers.

{{#ask: [[Category: MediaWiki extension]] [[Is developed by::Yaron Koren]]
 | ?Is developed by
 | distribution=yes
 | min=0
 | format=jqplotchart
 | mainlabel=-
}}

produces this:

Loading...

Read more in Inline queries, Displaying information, Help:Semantic templates and Result formats (Semantic-Mediawiki.org)

3.4 Query operators

SMW queries can include comparators and allows OR (disjunctions)

3.5 Troubleshooting

Use the debug option to test your #ask expression

{{#ask:[[Category:tutoriel]]
|?....
|format=debug
}}

Be aware that by default inline #ask only returns 50 results. Use the limit=.. parameter to change this. Alternatively reset the value of $smwgQDefaultLimit.

4 Special properties and compound data

(needs to be completed ....)

4.1 Special properties

Special properties are automatically generated by the system and have all sorts of functions. By default, these properties are not yet defined. In order to make use of them, we suggest the following procedure:

  1. List all properties using Special:Properties
  2. Hover the mouse over the red links, the wiki will tell if it's a special property
  3. Click on the red link
  4. Create with form
  5. Select type=text (not so sure about this....)

Good for debugging:

Understanding were you get your values from:

4.2 Compound data

(this section needs to be written)

SMW has a page-based approach. This makes it difficult with data like "the teacher owns 3 bananas", i.e. he "has bananas" and "he has 3"

You either can use subobjects or semantic internal objects to deal with this problem. Both have the same syntax, but work differently.

{{#subobject:Owns row|Owns fruit=bananas |Has quantity=4}}
{{#set_internal:Is row in possions|Owns fruit=tomatoes|Has quantity=4}}


5 Semantic MediaWiki software

Most semantic MediaWiki sites make use of a whole range of extensions that are built on top of the basic Semantic MediaWiki infrastructure. For exemple, a popular extension is Semantic Forms.

Read official documentation & download information:

Notice:: Read this old version, if you have an older MediaWiki or if you prefer manual installs.

5.1 Fresh install

(Summer 2015 for MW 1.25, updated summer 2016 for MW 1.26 and 1.27)

  • Install composer first if necessary (see below)
  • In the your installation (root) directory - and not the extension directory - type:
composer require mediawiki/semantic-media-wiki "~2.4"
composer require mediawiki/maps "*"
composer require mediawiki/semantic-maps "*"
composer require mediawiki/semantic-result-formats "*"
php maintenance/update.php
  • Verify: You composer.json file should have something like these lines
....
"mediawiki/semantic-media-wiki": "~2.4",
"mediawiki/maps": "*",
"mediawiki/semantic-maps": "*",
"mediawiki/semantic-result-formats": "*",
"mediawiki/sub-page-list": "~1.2",
"mediawiki/graph-viz": "^1.6",
"mediawiki/image-map": "@dev"
.....

Page Forms (formerly called Semantic Forms)

  • It is not recommended to install with Composer, rather install manually as explained in Page Forms
composer require mediawiki/semantic-forms
composer require mediawiki/page-forms
  • In LocalSettings.php:
// If needed, define a special namespace, can help if other custom extensions are used. Not necessary for fresh MediaWiki installs
$smwgNamespaceIndex = 108; // Adjust to yours
Note people [were talking about a ConfirmEdit issue, which I could not replicate (good for me...). Maybe because I did set an index ?
// This seems to be still required in summer 2016 for MW 1.26.3 and SMW 2.4.1
enableSemantics('edutechwiki.unige.ch'); // adjust to yours

5.2 Old MediaWiki 1.22 and SMW 1.9x installation/upgrade

After mid-november 2013, you should learn how to use composer, a PHP dependency manager.

5.2.1 Prerequisites

  • PHP 5.3.2+
  • MySQL 5.0.2+
  • CURL (you should have that)
  • MediaWiki 1.22 (nov 2013) or better.

If your server doesn't meet these requirements (in particular a new 1.22 MediaWiki), you should stop reading and find another source of information.

5.2.2 Install composer

If you run several wikis, it's probably best to install composer on system level:

 cd /some/src
 curl -sS https://getcomposer.org/installer | php
 mv composer.phar /usr/local/bin/composer

5.2.3 Prepare for updating SMW

  • Go to your MediaWiki installation (NOT the extension directory)
cd /your-mediawiki-install
  • If you already got SMW installed, kill it
rm -r extensions/SemanticMediaWiki
rm -r extensions/Validator 
rm -r extensions/DataValues
  • Same for SMW extensions, most should be killed (As of Jan 2014, SemanticForms is the notable exception, install it manually !!)
rm -r extensions/Maps/
rm -r extensions/SemanticMaps/
rm -r extensions/SemanticResultFormats

Changes to Localsettings.php

(1) kill all the lines that load SMW and required extensions. You really have to start clean, for example kill

require_once( "$IP/extensions/DataValues/DataValues.php" );
require_once( "$IP/extensions/Validator/Validator.php" );
include_once("$IP/extensions/SemanticMediaWiki/SemanticMediaWiki.php")

(2) Keep the following:

$smwgNamespaceIndex = 108; // Adjust to yours, in case other custom extensions were use before. Not necessary for fresh mediawiki installs
enableSemantics('edutechwiki.unige.ch'); // adjust to yours
  • Make damn sure that the line defining start of SMW namespaces (e.g. $smwgNamespaceIndex = 108; in our case) is the very first line of code that deals with SMW. E.g. if PHP sees the line enableSemantics(...) first, it will start numbering SMW extensions at 104 or something and you won't see your properties, forms, etc. defined in your existing wiki. You then may panic and do weird stuff that won't help your wiki very much.

(3) Comment out all other MediaWiki extensions

  • E.g. maps, semanticMaps, semanticresultformats, etc.

5.2.4 (Re)install SMW

  • Now get and install SemanticMediaWiki 1.9, plus its dependencies with composer
  • Again, do not cd to the extensions directory, keep sitting in the main MW installation directory !
composer require mediawiki/semantic-media-wiki "~2.0"
  • Alternatively, in case you want to use bleeding edge code (sometimes you should, sometimes not)
composer require mediawiki/semantic-media-wiki "dev-master"
  • In your MediaWiki installations you now will have:
A vendor directory
Additions to the extensions directory
  • There is no need to edit LocalSetting.php. All extensions will auto-load, i.e. MW 1.22 provides direct support for composer !! However, you later can edit LocalSettings.php to change settings.

5.2.5 (Re)configure SMW

php maintenance/update.php

5.2.6 Install (some) SMW extensions using the composer

As you can see, it is better not to provide any version information. These extensions should know what version to use with what SMW version.

composer require mediawiki/maps "*"
composer require mediawiki/semantic-maps "*"
composer require mediawiki/semantic-result-formats "*"
LocalSettings.php
  • Again, do not add any includes. These files are loaded (I believe) trough vendor/autoload.php

5.2.7 Add other SMW extension through GIT

cd extensions
// git clone https://gerrit.wikimedia.org/r/p/mediawiki/extensions/SemanticForms.git
git clone https://gerrit.wikimedia.org/r/p/mediawiki/extensions/PageForms
git clone https://gerrit.wikimedia.org/r/p/mediawiki/extensions/SemanticFormsInputs.git
git clone https://gerrit.wikimedia.org/r/p/mediawiki/extensions/SemanticDrilldown.git
git clone https://gerrit.wikimedia.org/r/p/mediawiki/extensions/AdminLinks.git

Of course, you then have to edit LocalSettings.php to include these files, for example it could look like this:

$smwgNamespaceIndex = 108;
enableSemantics('edutechwiki.unige.ch'); // adjust to yours
$smwgShowFactbox = SMW_FACTBOX_NONEMPTY;
// $smwgShowFactbox = SMW_FACTBOX_HIDDEN;
 
include_once("$IP/extensions/SemanticForms/SemanticForms.php");

# If one or more of your fields can contain internal links entered by users (e.g., "This is a [[cat]]")
$smwgLinksInValues = true;
 
# Semantic Drilldown. Needs yet another namespace
$sdgNamespaceIndex = 118;
include_once("$IP/extensions/SemanticDrilldown/SemanticDrilldown.php");
 
# Semantic Forms Inputs
# Is now available through composer (summer 2015)
# require_once("$IP/extensions/SemanticFormsInputs/SemanticFormsInputs.php");

# AdminLinks
include_once("$IP/extensions/AdminLinks/AdminLinks.php");

5.3 Upgrading MW 1.22+ / composer-based installations

  • Go to the base directory (not extensions or anything else !!)
cd /your/mediawiki_installation_directory
  • (Maybe) update the composer itself
composer self-update

For MW 1.22 or better ....

Typing the following won't work if you already have SMW installed

composer require mediawiki/semantic-media-wiki "~2.0"

In the root directory, edit file composer.json and change the SMW line:

"mediawiki/semantic-media-wiki": "~2.0",

If you do the same for the various Semantic Mediawiki extension, the JSON section could look something like this (but extensions and version numbers may change). It is best to follow instructions on each extension page as shown on the packagist web site or the mediawiki extension page.

 "require": {
		"php": ">=5.3.2",
		"psr/log": "1.0.0",
		"mediawiki/semantic-media-wiki": "~2.0",
		"mediawiki/semantic-result-formats": "*",
		"mediawiki/sub-page-list": "~1.1",
		"mediawiki/semantic-maps": "*",
		"mediawiki/maps": "*"
		"mediawiki/semantic-forms": "^3.4"
             },
  • Update all composer-managed extensions (including the ones that rely on SMW)
composer update
  • Run the MW update script (e.g. to change database tables)
php maintenance/update.php
  • Sometimes you also have to run the SMW update script, i.e. rebuild all tables
php extensions/SemanticMediaWiki/maintenance/SMW_refreshData.php -d 50 -v

5.4 Non standard setups

From the Readme file:

It is required to set the environment variable MW_INSTALL_PATH to the root of your MediaWiki installation first. This is also required if you use a symbolic link from ./extensions/SemanticMediaWiki to the actual installation directory of SMW. Setting environment variables is different for different operating systems and shells, but can normally be done from the command line right before the php call. On Bash(Linux), e.g., one can use the following call to execute SMW_setup.php with different MW location.

 export MW_INSTALL_PATH="/path/to/mediawiki" &&  php SMW_setup.php

5.5 Trouble

If you work with GIT and use the (default) "master" (the development branch), really make sure that all your extensions are match, e.g. you could the "master" development versions.

cd extenstions/extension_X
git pull origin master

It also may happen that you installed a new version that does not work using git pull. In that case:

git tag -l | sort -V
git checkout <tag name>

For example:

cd extensions/SemanticForms
git tag -l
git checkout 2.5.2

Otherwise, there are various support options:

5.6 Upgrading

After each version upgrade, you should launch the maintenance script. A slower version also can be run by admins from the special pages. Finally, if you just run the global MW update script in the "normal" maintenance directory, it also will trigger running the SMW update script.

cd extensions/SemanticMediaWiki/maintenance
php SMW_setup.php

Upgrading can go wrong, however since all SMW information (at least at our level of use) sits within wiki pages, you will not have to worry about messing up information that sits in semantic mediawiki database tables. If you made mistakes, e.g. killed lines defining namespaces index numbers in LocalSettings.php, simply rebuild all the SMW-related tables. SMW Database tables are just for performance, i.e. they are a secondary store. Just to make sure: Do never ever mess up other tables, we just talk about SMW tables here !

Furthermore, it cannot hurt to dump the whole database before you upgrade the MW software or just the SMW extensions. I usually do not do that, since I first upgrade a test server or a less critical production wiki. We also got daily backups if things really become bad. The main problem I had with MW/SMW upgrades is just that some less critical extensions stop working. I then usually try to find a fix and if I don't, I'll trash these minor extensions.

See the next point about rebuilding the SMW databases !

5.7 Cleaning up / repairing the Semantic MediaWiki tables

Disclaimer: If the following kills your wiki, erases your hard disk and burns down your office, do not blame me ! Read the documentation at the beginning of the script and evaluate the risks !

Let's assume that you created lots of useless parameters, that you created weird templates that produce illegal parameters etc. Time to clean up ! Although you could use the tools available in wiki's special pages, it maybe time to play with the maintenance scripts.

Read https://www.semantic-mediawiki.org/wiki/Help:RebuildData.php RebuildData.php

The rebuild data script will rebuild the database from SMW information found in pages.

The following script, if you use the -f option, will empty all semantic mediawiki tables and create the data again. Since all information is stored in both normal wiki pages and semantic MediaWiki namespaced pages, e.g. property:, the tables will be rebuilt by going through all wikipages in all namespaces. In other words, by erasing all the database tables, you should not loose any information.

-f - kill everything
-d 100 - parse a page every 100 milliseconds
-v - be verbose
cd SemanticMediaWiki/maintenance
php rebuildData.php -f -d 100 -v 

The script may choke on a page with a broken extension. E.g. in this wiki it was UML activity diagram. This page has ID=4219. If such a thing happens, just move on. Restart the script with the next page, e.g.

php rebuildData.php -d 100 -v -s 4220

Exemple, refreshing without killing anything, doing it a bit faster and without verbose output.

 php rebuildData.php -d 50

The refreshData script is deprecated !!

You will notice that all bad properties are gone now if you look at special:properties

5.8 The SMW database updating process

The SMW database should update each time a user does something.

To speed this, up you could run cronjobs.

Read Help:Maintenance

5.9 Semantic MediaWiki extensions

  • Semantic Drilldown provides a page for drilling down through a site's data, using categories and filters on semantic properties.
  • Semantic Watchlist extends Semantic MediaWiki by adding the capability to watch/follow sets of properties for groups of pages (that can be specified with categories and namespaces).
  • Semantic Extra Special Properties
    • Will add some more built-in properties to pages, so that you could extract more information from all pages, e.g. contributing users, views, etc. (not tested so far)
Other useful extensions to use with SMW
  • MyVariables. This simple extensions defines some extra variables (magic words) you could use, in particular {{CURRENTUSER}} that you could use for reporting/tracking applications.
  • External Data (aka "ED"), allows MediaWiki pages to retrieve, filter, and format structure data from one or more sources. These sources can include an external URLs, a regular wiki page, an uploaded file, an LDAP directory and a database.

5.10 Data import/export

  • Support for RDF triplestores (via SPARQL)

5.11 SMW packaged services and distributions

  • SMW+ is a prepackaged version of MediaWiki/Semantic Wiki described as "semantic enterprise wiki that lets you create and share knowledge with your team." Both a free version and a pro version are available.

5.12 Programming SMW extensions

Read:

Code documentation:

Tutorials and examples:

6 Links

6.1 Official other important SMW sites

6.2 Events

6.3 Manuals and introductions

See also: User manual, which includes additional links

Official
  • Quick Reference Guide: PNG or PDF
  • Help:Repairing SMW's data. Since all SMW data is stored in wiki pages, data cannot be truly lost or corrupted. You can easily rebuild the database tables.
  • The API includes some specific SMW actions]
Tips
  • Tips at Referata.com

6.4 Tutorials

  • The Semantic Puzzle, Short Semantic MediaWiki Tutorial (with link to sandbox), November 5, 2008 by Thomas Schandl (but the demo wiki is broken as of July 2013)

6.5 Various

  • blog (Jeroen De Dauw, a SWM key developer, interesting posts)
  • SMWCon also known as the Semantic MediaWiki Conference, is a twice-yearly gathering for users, developers and enthusiasts of Semantic MediaWiki,

6.6 Semantic MediaWiki sites

Indexes (listed sites below were more or less randomly chosen)
Plants
  • Gardenology.org - Plant & Garden Wiki Encyclopedia is a complete plant and garden wiki encyclopedia. So far we have 21,980 plant entries and other articles written and edited by gardeners from around the globe (June 2013).
  • Practical Plants. Practical Plants is a collaboratively edited encyclopedia and database of information on plants cultivated with a practical intention. Over 7400 plant articles covering edible, medicinal and material uses, propagation and cultivation information, plant associations and polycultures, and everything else you need to know to grow and benefit from practical plants.
  • food finds
  • Pest Information Wiki includes 117299 research publications and other information on pests, diseases and weeds. Organized by the International Society for Pest Information (ISPI)
Biology
  • SNPedia, a wiki investigating human genetics.
Research and artifacts
Computer science and digital design/fabrication
  • AIFB Web Portal, at Institute of Applied Informatics and Formal Description Methods (AIFB) at Karlsruhe Institute of Technology. (Includes prime contributors to the Semantic MediaWiki code).
  • catalogs useful free software that runs under free operating systems
  • Hackerspaces. Quote: are community-operated physical places, where people can meet and work on their projects. This website is for Anyone and Everyone who wants to share their hackerspace stories and questions with the global hackerspaces community.
  • Domotiki.eu, base de connaissance sur la domotique : Matériels, Logiciels, Protocoles, Revendeurs, Installateurs, Constructeurs...

7 Bibliography

See also: Semantic MediaWiki publications at semantic-mediawiki.org

  • Bao, J., Ding, L., & Hendler, J. (2008). Knowledge representation and query in semantic mediawiki: A formal study. Tetherless World Constellation (RPI) Technical Report. PDF. (I found this to be a good introduction to the formal aspects of SMW, although some parts are quite heavy..- Daniel K. Schneider (talk) 12:27, 28 June 2013 (CEST))
  • Boulos, Maged N. Kamel (2009). Semantic Wikis: A Comprehensible Introduction with Examples from the Health Sciences, Journal of Emerging Technologies in Web Intelligence, Vol 1, No 1 (2009), 94-96, Aug 2009 doi:10.4304/jetwi.1.1.94-96
  • Dengler, Frank and Hans-Jörg Happel. 2010. Collaborative modeling with semantic MediaWiki. In Proceedings of the 6th International Symposium on Wikis and Open Collaboration (WikiSym '10). ACM, New York, NY, USA, Article 23 , 2 pages. DOI=10.1145/1832772.1832802 http://doi.acm.org/10.1145/1832772.1832802
  • García, R. R., Gil, R. R., Gimeno, J. M., Granollers, T. T., López, J. M., Oliva, M. M., & Pascual, A. A. (2010). Semantic wiki for quality management in software development projects. IET Software, 4(6), 386-395. doi:10.1049/iet-sen.2010.0044
  • Krötzsch, Markus; Denny Vrandecic, Max Völkel, Heiko Haller & Rudi Studer. Semantic Wikipedia. (2007). Journal of Web Semantics 5, pp. 251-261. Elsevier 2007.
  • Krötzsch. M, D. Vrandecic, M. Völkel, H. Haller, and R. Studer. Semantic Wikipedia (ESWC2006 demo), European Semantic Web Conference, ESWC2006, Budva, Montenegro. Best Poster Award.
  • Krötzsch, M., & Vrandecic, D. (2009). Semantic wikipedia. In Social Semantic Web (pp. 393-421). Springer Berlin Heidelberg.
  • Krötzsch, M., & Vrandečić, D. (2011). Semantic mediawiki. In Foundations for the Web of Information and Services (pp. 311-326). Springer Berlin Heidelberg.
  • Reutelshoefer, J., Lemmerich, F., Haupt, F., & Baumeister, J. (2009). An extensible semantic wiki architecture. In 4th Semantic Wiki Workshop (SemWiki). PDF Preprint ?
  • Sateli, B., S. S. Rajivelu, E. Angius, and R. Witte, "ReqWiki: A Semantic System for Collaborative Software Requirements Engineering", The 8th International Symposium on Wikis and Open Collaboration (WikiSym 2012), Linz, Austria : ACM, 08/2012 (Describes ReWiki, a software requirements engineerin "bundle" based on SMW)
  • Sateli, B., E. Angius, S. S. Rajivelu, and R. Witte, "Can Text Mining Assistants Help to Improve Requirements Specifications?", Mining Unstructured Data (MUD 2012), Kingston, Ontario, Canada, October 17, 2012.
  • Schaffert, Sebastian, Joachim Baumeister, François Bry and Malte Kiesel (2008). Semantic Wikis. IEEE Software, 25 (4) 8-11.
  • Schaffert, Sebastian; Diana Bischof, Tobias Bürger, Andreas Gruber, Wolf Hilzensauer and Sandra Schaffert (2006). Learning with Semantic Wikis. In: Proceedings of the 1st Workshop on Semantic Wikis
  • Rutledge, Lloyd and Rineke Oostenrijk (2011). Applying and Extending Semantic Wikis for Semantic Web Courses. International Workshop on eLearning Approaches for the Linked Data Age, Heraclion, Crete, Greece.
  • Yao, W. (2012). Specifying semantic information on functional requirements. MA Thesis. University of Tampere (PDF)
Facts about "Semantic MediaWiki"
Depends onValidator + and ParamProcessor +
Grading scale6 +
Has acronymSMW +
Has addressOxford, England +
Has descriptionSemantic MediaWiki is an extension for managing structured data in your wiki and for querying that data to create dynamic representations: tables, timelines, maps, lists, etc. +
Has last revision number1.9.2 (40ea19e) +
Has location51° 45' 7", -1° 15' 28"Latitude: 51.752022222222
Longitude: -1.257725
+
Has nameSemantic MediaWiki +
Has statusstable +
Has support websitehttp://www.semantic-mediawiki.org/wiki/Semantic_MediaWiki +
Has websitehttp://www.semantic-mediawiki.org/wiki/Semantic_MediaWiki +
Is aWiki +
Is developed byMarkus Krötzsch +, Denny Vrandecic +, Jeroen De Dauw + and others +
Is related toSemantic Drilldown +, Semantic Forms +, Semantic Forms Inputs +, Semantic Maps + and Semantic Result Formats +
Needs MediaWiki versionsAny recent version. However, we suggest using MW 1.22 (dec 2013). This version includes support for Composer, a dependency manager that will ease installation. +
Supports languagesMany +
Uses programming languagePHP +
Was first released onJanuary 1, 2005 +
Was last editedMay 2, 2014 +
Was last released onApril 28, 2014 +
Has subobject
"Has subobject" is a predefined property representing a container construct and is provided by Semantic MediaWiki.
Semantic MediaWiki#Owns_row +