MediaWiki is the software from the MediaWiki foundation that powers websites like Wikipedia or laussy.org, as well as other various wikis that we run or where we collaborate.
Unless you care about the underlying technical details, there is little to know about MediaWiki besides the pun on media and wiki to make up the names of both the organization and its product. If you care about the software, read on.
This page is not about the wiki itself, which is the language to feed MediaWiki with.
This is a long process that dispatch data back and forth from the database and format the output to the screen.
Mediawiki, the software that organizes the data and arrange its transformation into HTML, distributes its content into different namespaces. The main content is in the Main namespace which ha no prefix. On most Wikis, you have the User: and the Talk: namespaces.
This is an example of a database querry for BlogTitles:
SELECT p.page_id, p.page_title, wp.wlp_title, wp.wlp_updated, wp.wlp_authors
FROM page p
JOIN wikilog_posts wp ON p.page_id = wp.wlp_page
WHERE p.page_namespace = 100
AND wp.wlp_authors LIKE '%Fabrice%'
ORDER BY wp.wlp_updated DESC
LIMIT 50;
+---------+-----------------------------------------+---------------------------------+----------------+--------------------------+
| page_id | page_title | wlp_title | wlp_updated | wlp_authors |
+---------+-----------------------------------------+---------------------------------+----------------+--------------------------+
| 17627 | Sotito's_Garden/The_ideal_garden | The ideal garden | 20250330133252 | a:1:{s:7:"Fabrice";i:2;} |
| 18328 | Fabrice/Brooding_from_the_Cyclades | Brooding from the Cyclades | 20250301151028 | a:1:{s:7:"Fabrice";i:2;} |
| 17653 | Fabrice/828_days_into_the_3rd_World_War | 828 days into the 3rd World War | 20250301151018 | a:1:{s:7:"Fabrice";i:2;} |
| 17584 | Fabrice/Two_years_of_war_in_Ukraine | Two years of war in Ukraine | 20250301151007 | a:1:{s:7:"Fabrice";i:2;} |
| 16855 | Fabrice/Napoleon,_Hitler,_Prigozhin | Napoleon, Hitler, Prigozhin | 20250301150957 | a:1:{s:7:"Fabrice";i:2;} |
+---------+-----------------------------------------+---------------------------------+----------------+--------------------------+
This page is still largely in progress.
I am currently running with V°1.43.
Upgrading has a manual step. The core file includes/specials/helpers/ImportReporter.php carries a local patch—the $wgLaussyImportNullRevision guard, which stops every action=import from stacking a bookkeeping "1 revision imported" revision on top of the imported one; that suppression is what lets llw2lw mirror the local history online with its true dates. Any MediaWiki upgrade overwrites the file silently, and the tell is those markers reappearing in online page histories. Re-apply the guard—a pristine 1.43.1 copy sits in ~/comp/lw/ImportReporter.php.orig-1.43.1, the patched version being the live local file—and pushcode it again; the full story is under llw2lw.
A double redirect is when you redirect (refer to) a page which itself redirects to another. In that case, to avoid infinite loops, the user typically gets confronted with the annoying . The pages can be identified through the Special:DoubleRedirects and (even worse case) Special:BrokenRedirects pages. This can be fixed, e.g., Page A → Page B → Page C should be such that Page A → Page C, so that no unnecessary transit by Page B is necessary. This can be done by hand, or if there are many, it can be automatized by setting $wgFixDoubleRedirects to true. You may have to run php maintenance/runJobs.php yourself.
Downloading from MediaWiki's Extensions web and following the instruction is the basic way. More convenient is:
cd extensions/ git clone https://gerrit.wikimedia.org/r/mediawiki/extensions/YouTube
Then check the version:
cd YouTube git tab
Look for a tag like REL1_43, and if present:
git checkout REL1_43
And then add in LocalSettings.php the link to new functionalities: wfLoadExtension( 'YouTube' );