From 44020e254c9fa3b60b8f0874df84490ba99bb464 Mon Sep 17 00:00:00 2001
From: Sam Reed <reedy@users.mediawiki.org>
Date: Wed, 24 Aug 2011 13:03:03 +0000
Subject: [PATCH] Merge the iwtransclusion branch back into trunk

Hexmode fixed broken unit tests in revisions after last time
---
 includes/AutoLoader.php                       |   3 +
 includes/BacklinkCache.php                    |  20 +
 includes/DefaultSettings.php                  |  30 +-
 includes/EditPage.php                         |  43 +-
 includes/GlobalUsageQuery.php                 | 368 ++++++++++++++++++
 includes/Linker.php                           |  36 ++
 includes/LinksUpdate.php                      | 145 +++++++
 includes/OutputPage.php                       |   9 +
 includes/Revision.php                         |  43 +-
 includes/SpecialPageFactory.php               |   2 +
 includes/Title.php                            |  49 ++-
 includes/WikiPage.php                         |  57 ++-
 includes/cache/HTMLCacheUpdate.php            |  49 +++
 includes/db/Database.php                      |  33 ++
 includes/installer/MysqlUpdater.php           |   3 +
 includes/installer/SqliteUpdater.php          |   5 +
 includes/interwiki/Interwiki.php              | 165 ++++++++
 includes/parser/Parser.php                    | 100 ++---
 includes/parser/ParserOutput.php              |  29 ++
 includes/parser/Preprocessor_DOM.php          |   3 +-
 includes/parser/Preprocessor_Hash.php         |   1 +
 includes/specials/SpecialGlobalFileUsage.php  | 224 +++++++++++
 .../specials/SpecialGlobalTemplateUsage.php   | 207 ++++++++++
 languages/messages/MessagesEn.php             |  29 ++
 languages/messages/MessagesQqq.php            |  10 +
 .../archives/patch-globalinterwiki.sql        |  10 +
 .../archives/patch-globalnamespaces.sql       |  14 +
 .../archives/patch-globaltemplatelinks.sql    |  36 ++
 maintenance/language/messages.inc             |   3 +
 maintenance/tables.sql                        |  64 +++
 30 files changed, 1713 insertions(+), 77 deletions(-)
 create mode 100644 includes/GlobalUsageQuery.php
 create mode 100644 includes/specials/SpecialGlobalFileUsage.php
 create mode 100644 includes/specials/SpecialGlobalTemplateUsage.php
 create mode 100644 maintenance/archives/patch-globalinterwiki.sql
 create mode 100644 maintenance/archives/patch-globalnamespaces.sql
 create mode 100644 maintenance/archives/patch-globaltemplatelinks.sql

diff --git a/includes/AutoLoader.php b/includes/AutoLoader.php
index bd3d9d0523..62da731aef 100644
--- a/includes/AutoLoader.php
+++ b/includes/AutoLoader.php
@@ -539,6 +539,7 @@ $wgAutoloadLocalClasses = array(
 	'BmpHandler' => 'includes/media/BMP.php',
 	'DjVuHandler' => 'includes/media/DjVu.php',
 	'Exif' => 'includes/media/Exif.php',
+	'GlobalUsageQuery' => 'includes/GlobalUsageQuery.php',
 	'FormatExif' => 'includes/media/FormatMetadata.php',
 	'FormatMetadata' => 'includes/media/FormatMetadata.php',
 	'GIFHandler' => 'includes/media/GIF.php',
@@ -752,6 +753,8 @@ $wgAutoloadLocalClasses = array(
 	'SpecialEmailUser' => 'includes/specials/SpecialEmailuser.php',
 	'SpecialExport' => 'includes/specials/SpecialExport.php',
 	'SpecialFilepath' => 'includes/specials/SpecialFilepath.php',
+	'SpecialGlobalFileUsage' => 'includes/specials/SpecialGlobalFileUsage.php',
+	'SpecialGlobalTemplateUsage' => 'includes/specials/SpecialGlobalTemplateUsage.php',
 	'SpecialImport' => 'includes/specials/SpecialImport.php',
 	'SpecialListFiles' => 'includes/specials/SpecialListfiles.php',
 	'SpecialListGroupRights' => 'includes/specials/SpecialListgrouprights.php',
diff --git a/includes/BacklinkCache.php b/includes/BacklinkCache.php
index 2263051456..978abecad3 100644
--- a/includes/BacklinkCache.php
+++ b/includes/BacklinkCache.php
@@ -174,6 +174,25 @@ class BacklinkCache {
 		return $ta;
 	}
 
+	/**
+	 * Get the distant backtemplatelinks for the table globaltemplatelinks. Cached in process memory only.
+	 * @return ResultWrapper list of distant pages that use the local title
+	 */
+	public function getDistantTemplateLinks( ) {
+		global $wgGlobalDatabase, $wgLocalInterwiki;
+		
+		$dbr = $dbr = wfGetDB( DB_SLAVE, array(), $wgGlobalDatabase );
+		$res = $dbr->select(
+			array( 'globaltemplatelinks', 'globalinterwiki' ),
+			array( 'gtl_from_wiki', 'gtl_from_page', 'gtl_from_title', 'giw_prefix' ),
+			array( 'gtl_to_prefix' => $wgLocalInterwiki, 'gtl_to_title' => $this->title->getDBkey( ) ),
+			__METHOD__,
+			null,
+			array( 'gtl_from_wiki = giw_wikiid' )
+		);
+		return $res;
+	}
+
 	/**
 	 * Get the field name prefix for a given table
 	 * @param $table String
@@ -185,6 +204,7 @@ class BacklinkCache {
 			'categorylinks' => 'cl',
 			'templatelinks' => 'tl',
 			'redirect'      => 'rd',
+			'globaltemplatelinks' => 'gtl',
 		);
 
 		if ( isset( $prefixes[$table] ) ) {
diff --git a/includes/DefaultSettings.php b/includes/DefaultSettings.php
index 83078bc1fb..d9e0de72df 100644
--- a/includes/DefaultSettings.php
+++ b/includes/DefaultSettings.php
@@ -2983,12 +2983,34 @@ $wgExpensiveParserFunctionLimit = 100;
 $wgPreprocessorCacheThreshold = 1000;
 
 /**
- * Enable interwiki transcluding.  Only when iw_trans=1.
+ * Enable interwiki transcluding.  Only when iw_trans=1 in the interwiki table.
+ * If the interwiki prefix is associated with a wiki ID in the interwiki table,
+ * then the distant templates will be retrieved in the distant DB. If there is
+ * no wiki ID but a API URL for that prefix, the distant templates will be
+ * retrieved using the API and cached in memcached.
  */
-$wgEnableScaryTranscluding = false;
+$wgEnableInterwikiTranscluding = false;
 
 /**
- * Expiry time for interwiki transclusion
+ * If $wgEnableInterwikiTranscluding is set to true and if an interwiki prefix
+ * is associated with a wiki ID, then, this option should be set to true to
+ * enable the cache invalidation of the distant pages when the local templates
+ * are edited and also to display the list of the distant templates used by
+ * the local pages. Enabling this requires to set up a global shared database
+ * (see next option $wgGlobalDatabase). 
+ */
+$wgEnableInterwikiTemplatesTracking = false;
+
+/**
+ * If $wgEnableInterwikiTemplatesTracking is set to true, this option should
+ * contain the wiki ID of the database that hosts the globaltemplatelinks table.
+ */
+$wgGlobalDatabase = ''; 
+
+/**
+ * If $wgEnableInterwikiTranscluding is set to true and if an interwiki
+ * prefix is associated with an API URL and no wiki ID, this will be
+ * the expiry time for the transcluded templates cached in memcached.
  */
 $wgTranscludeCacheExpiry = 3600;
 
@@ -5131,6 +5153,8 @@ $wgSpecialPageGroups = array(
 	'Export'                    => 'pagetools',
 	'Import'                    => 'pagetools',
 	'Whatlinkshere'             => 'pagetools',
+	'GlobalFileUsage'           => 'pagetools',
+	'GlobalTemplateUsage'       => 'pagetools',
 
 	'Statistics'                => 'wiki',
 	'Version'                   => 'wiki',
diff --git a/includes/EditPage.php b/includes/EditPage.php
index 28032da57e..20a1f4834a 100644
--- a/includes/EditPage.php
+++ b/includes/EditPage.php
@@ -1313,7 +1313,7 @@ class EditPage {
 	 *     during form output near the top, for captchas and the like.
 	 */
 	function showEditForm( $formCallback = null ) {
-		global $wgOut, $wgUser;
+		global $wgOut, $wgUser, $wgEnableInterwikiTranscluding, $wgEnableInterwikiTemplatesTracking;
 
 		wfProfileIn( __METHOD__ );
 
@@ -1347,7 +1347,6 @@ class EditPage {
 			$toolbar = '';
 		}
 
-
 		$wgOut->addHTML( $this->editFormPageTop );
 
 		if ( $wgUser->getOption( 'previewontop' ) ) {
@@ -1359,6 +1358,9 @@ class EditPage {
 		$templates = $this->getTemplates();
 		$formattedtemplates = Linker::formatTemplates( $templates, $this->preview, $this->section != '');
 
+		$distantTemplates = $this->getDistantTemplates();
+		$formattedDistantTemplates = Linker::formatDistantTemplates( $distantTemplates, $this->preview, $this->section != '' );
+
 		$hiddencats = $this->mArticle->getHiddenCategories();
 		$formattedhiddencats = Linker::formatHiddenCategories( $hiddencats );
 
@@ -1457,6 +1459,21 @@ HTML
 <div class='templatesUsed'>
 {$formattedtemplates}
 </div>
+HTML
+);
+
+		if ( $wgEnableInterwikiTranscluding && $wgEnableInterwikiTemplatesTracking ) {
+					$wgOut->addHTML( <<<HTML
+{$this->editFormTextAfterTools}
+<div class='distantTemplatesUsed'>
+{$formattedDistantTemplates}
+</div>
+HTML
+);
+		}
+
+		$wgOut->addHTML( <<<HTML
+{$this->editFormTextAfterTools}
 <div class='hiddencats'>
 {$formattedhiddencats}
 </div>
@@ -2118,6 +2135,28 @@ HTML
 		}
 	}
 
+	function getDistantTemplates() {
+		global $wgEnableInterwikiTemplatesTracking;
+		if ( !$wgEnableInterwikiTemplatesTracking ) {
+			return array( );
+		}
+		if ( $this->preview || $this->section != '' ) {
+			$templates = array();
+			if ( !isset( $this->mParserOutput ) ) return $templates;
+			$templatesList = $this->mParserOutput->getDistantTemplates();
+			foreach( $templatesList as $prefix => $templatesbyns ) {
+				foreach( $templatesbyns as $ns => $template ) {
+					foreach( array_keys( $template ) as $dbk ) {
+						$templates[] = Title::makeTitle( $ns, $dbk, null, $prefix );
+					}
+				}
+			}
+			return $templates;
+		} else {
+			return $this->mArticle->getUsedDistantTemplates();
+		}
+	}
+
 	/**
 	 * Call the stock "user is blocked" page
 	 */
diff --git a/includes/GlobalUsageQuery.php b/includes/GlobalUsageQuery.php
new file mode 100644
index 0000000000..8e4ad35126
--- /dev/null
+++ b/includes/GlobalUsageQuery.php
@@ -0,0 +1,368 @@
+<?php
+/**
+ * A helper class to query the globalimagelinks table
+ * 
+ */
+class GlobalUsageQuery {
+	private $limit = 50;
+	private $offset;
+	private $hasMore = false;
+	private $filterLocal = false;
+	private $result;
+	private $continue;
+	private $reversed = false;
+	private $target = null;
+	
+	/**
+	 * @param $target mixed Title or db key, or array of db keys of target(s)
+	 */
+	public function __construct( $target ) {
+		global $wgGlobalDatabase;
+		$this->db = wfGetDB( DB_SLAVE, array(), $wgGlobalDatabase );
+		if ( $target instanceof Title && $target->getNamespace( ) == NS_FILE ) {
+			$this->target = $target->getDBKey();
+		} else {
+			$this->target = $target;
+		}
+		$this->offset = array();
+
+	}
+
+	/**
+	 * Set the offset parameter
+	 *
+	 * @param $offset string offset
+	 * @param $reversed bool True if this is the upper offset
+	 */
+	public function setOffset( $offset, $reversed = null ) {
+		if ( !is_null( $reversed ) ) {
+			$this->reversed = $reversed;
+		}
+		
+		if ( !is_array( $offset ) ) {
+			$offset = explode( '|', $offset );
+		}
+
+		if ( count( $offset ) == 3 ) {
+			$this->offset = $offset;
+			return true;
+		} else {
+			return false;
+		}
+	}
+	/**
+	 * Return the offset set by the user
+	 *
+	 * @return array offset
+	 */
+	public function getOffsetString() {
+		return implode( '|', $this->offset );
+	}
+	/**
+	 * Is the result reversed
+	 * 
+	 * @return bool
+	 */
+	public function isReversed() {
+		return $this->reversed;
+	}
+	
+	/**
+	 * Returns the string used for continuation in a file search
+	 * 
+	 * @return string
+	 * 
+	 */
+	public function getContinueFileString() {
+		if ( $this->hasMore() ) {
+			return "{$this->lastRow->gil_to}|{$this->lastRow->gil_wiki}|{$this->lastRow->gil_page}";
+		} else {
+			return '';
+		}
+	}
+	
+	/**
+	 * Returns the string used for continuation in a template search
+	 *
+	 * @return string
+	 *
+	 */
+	public function getContinueTemplateString() {
+		if ( $this->hasMore() ) {
+			return "{$this->lastRow->gtl_to_title}|{$this->lastRow->gtl_from_wiki}|{$this->lastRow->gtl_from_page}";
+		} else {
+			return '';
+		}
+	}
+	
+	/**
+	 * Set the maximum amount of items to return. Capped at 500.
+	 *
+	 * @param $limit int The limit
+	 */
+	public function setLimit( $limit ) {
+		$this->limit = min( $limit, 500 );
+	}
+	/**
+	 * Returns the user set limit
+	 */
+	public function getLimit() {
+		return $this->limit;
+	}
+
+	/**
+	 * Set whether to filter out the local usage
+	 */
+	public function filterLocal( $value = true ) {
+		$this->filterLocal = $value;
+	}
+
+	/**
+	 * Executes the query for a file search
+	 */
+	public function searchTemplate() {
+		global $wgLocalInterwiki;
+
+		/* Construct a where clause */
+		// Add target template(s)
+		$where = array( 'gtl_to_prefix' => $wgLocalInterwiki,
+						'gtl_to_namespace' => $this->target->getNamespace( ),
+						'gtl_to_title' => $this->target->getDBkey( )
+				);
+
+		// Set the continuation condition
+		$order = 'ASC';
+		if ( $this->offset ) {
+			$qTo = $this->db->addQuotes( $this->offset[0] );
+			$qWiki = $this->db->addQuotes( $this->offset[1] );
+			$qPage = intval( $this->offset[2] );
+
+			// Check which limit we got in order to determine which way to traverse rows
+			if ( $this->reversed ) {
+				// Reversed traversal; do not include offset row
+				$op1 = '<';
+				$op2 = '<';
+				$order = 'DESC';
+			} else {
+				// Normal traversal; include offset row
+				$op1 = '>';
+				$op2 = '>=';
+				$order = 'ASC';
+			}
+
+			$where[] = "(gtl_to_title $op1 $qTo) OR " .
+				"(gtl_to_title = $qTo AND gtl_from_wiki $op1 $qWiki) OR " .
+				"(gtl_to_title = $qTo AND gtl_from_wiki = $qWiki AND gtl_from_page $op2 $qPage)";
+		}
+
+		/* Perform select (Duh.) */
+		$res = $this->db->select(
+				array(
+					'globaltemplatelinks',
+					'globalnamespaces'
+				),
+				array(
+					'gtl_to_title',
+					'gtl_from_wiki',
+					'gtl_from_page',
+					'gtl_from_namespace',
+					'gtl_from_title'
+				),
+				$where,
+				__METHOD__,
+				array(
+					'ORDER BY' => "gtl_to_title $order, gtl_from_wiki $order, gtl_from_page $order",
+					// Select an extra row to check whether we have more rows available
+					'LIMIT' => $this->limit + 1,
+				),
+				array(
+					'gtl_from_namespace = gn_namespace'
+				)
+		);
+
+		/* Process result */
+		// Always return the result in the same order; regardless whether reversed was specified
+		// reversed is really only used to determine from which direction the offset is
+		$rows = array();
+		foreach ( $res as $row ) {
+			$rows[] = $row;
+		}
+		if ( $this->reversed ) {
+			$rows = array_reverse( $rows );
+		}
+
+		// Build the result array
+		$count = 0;
+		$this->hasMore = false;
+		$this->result = array();
+		foreach ( $rows as $row ) {
+			$count++;
+			if ( $count > $this->limit ) {
+				// We've reached the extra row that indicates that there are more rows
+				$this->hasMore = true;
+				$this->lastRow = $row;
+				break;
+			}
+
+			if ( !isset( $this->result[$row->gtl_to_title] ) ) {
+				$this->result[$row->gtl_to_title] = array();
+			}
+			if ( !isset( $this->result[$row->gtl_to_title][$row->gtl_from_wiki] ) ) {
+				$this->result[$row->gtl_to_title][$row->gtl_from_wiki] = array();
+			}
+
+			$this->result[$row->gtl_to_title][$row->gtl_from_wiki][] = array(
+				'template'	=> $row->gtl_to_title,
+				'id' => $row->gtl_from_page,
+				'namespace' => $row->gn_namespacetext,
+				'title' => $row->gtl_from_title,
+				'wiki' => $row->gtl_from_wiki,
+			);
+		}
+	}
+
+	/**
+	 * Executes the query for a template search
+	 */
+	public function searchFile() {
+		/* Construct a where clause */
+		// Add target image(s)
+		$where = array( 'gil_to' => $this->target );
+		
+		if ( $this->filterLocal ) {
+			// Don't show local file usage
+			$where[] = 'gil_wiki != ' . $this->db->addQuotes( wfWikiId() );
+		}
+
+		// Set the continuation condition
+		$order = 'ASC';
+		if ( $this->offset ) {
+			$qTo = $this->db->addQuotes( $this->offset[0] );
+			$qWiki = $this->db->addQuotes( $this->offset[1] );
+			$qPage = intval( $this->offset[2] );
+			
+			// Check which limit we got in order to determine which way to traverse rows
+			if ( $this->reversed ) {
+				// Reversed traversal; do not include offset row
+				$op1 = '<';
+				$op2 = '<';
+				$order = 'DESC';
+			} else {
+				// Normal traversal; include offset row
+				$op1 = '>';
+				$op2 = '>=';
+				$order = 'ASC';
+			}
+			
+			$where[] = "(gil_to $op1 $qTo) OR " .
+				"(gil_to = $qTo AND gil_wiki $op1 $qWiki) OR " .
+				"(gil_to = $qTo AND gil_wiki = $qWiki AND gil_page $op2 $qPage)";
+		}
+
+		/* Perform select (Duh.) */
+		$res = $this->db->select( 'globalimagelinks',
+				array(
+					'gil_to',
+					'gil_wiki',
+					'gil_page',
+					'gil_page_namespace',
+					'gil_page_title'
+				),
+				$where,
+				__METHOD__,
+				array(
+					'ORDER BY' => "gil_to $order, gil_wiki $order, gil_page $order",
+					// Select an extra row to check whether we have more rows available
+					'LIMIT' => $this->limit + 1,
+				)
+		);
+
+		/* Process result */
+		// Always return the result in the same order; regardless whether reversed was specified
+		// reversed is really only used to determine from which direction the offset is
+		$rows = array();
+		foreach ( $res as $row ) {
+			$rows[] = $row;
+		}
+		if ( $this->reversed ) {
+			$rows = array_reverse( $rows );
+		}
+		
+		// Build the result array
+		$count = 0;
+		$this->hasMore = false;
+		$this->result = array();
+		foreach ( $rows as $row ) {
+			$count++;
+			if ( $count > $this->limit ) {
+				// We've reached the extra row that indicates that there are more rows
+				$this->hasMore = true;
+				$this->lastRow = $row;
+				break;
+			}
+
+			if ( !isset( $this->result[$row->gil_to] ) ) {
+				$this->result[$row->gil_to] = array();
+			}
+			if ( !isset( $this->result[$row->gil_to][$row->gil_wiki] ) ) {
+				$this->result[$row->gil_to][$row->gil_wiki] = array();
+			}
+
+			$this->result[$row->gil_to][$row->gil_wiki][] = array(
+				'image'	=> $row->gil_to,
+				'id' => $row->gil_page,
+				'namespace' => $row->gil_page_namespace,
+				'title' => $row->gil_page_title,
+				'wiki' => $row->gil_wiki,
+			);
+		}
+	}
+
+	/**
+	 * Returns the result set. The result is a 4 dimensional array
+	 * (file, wiki, page), whose items are arrays with keys:
+	 *   - image or template: File name or template name 
+	 *   - id: Page id
+	 *   - namespace: Page namespace text
+	 *   - title: Unprefixed page title
+	 *   - wiki: Wiki id
+	 * 
+	 * @return array Result set
+	 */
+	public function getResult() {
+		return $this->result;
+	}
+	/**
+	 * Returns a 3 dimensional array with the result of the first file. Useful
+	 * if only one resource was queried.
+	 * 
+	 * For further information see documentation of getResult()
+	 * 
+	 * @return array Result set
+	 */
+	public function getSingleResult() {
+		if ( $this->result ) {
+			return current( $this->result );
+		} else {
+			return array();
+		}
+	}
+
+	/**
+	 * Returns whether there are more results
+	 *
+	 * @return bool
+	 */
+	public function hasMore() {
+		return $this->hasMore;
+	}
+
+	/**
+	 * Returns the result length
+	 * 
+	 * @return int
+	 */
+	public function count() {
+		return count( $this->result );
+	}
+}
diff --git a/includes/Linker.php b/includes/Linker.php
index f1fb577174..a1cf6a6329 100644
--- a/includes/Linker.php
+++ b/includes/Linker.php
@@ -1645,6 +1645,42 @@ class Linker {
 		return $outText;
 	}
 
+	/**
+	 * Returns HTML for the "templates used on this page" list.
+	 *
+	 * @param $templates Array of templates from Article::getUsedTemplate
+	 * or similar
+	 * @param $preview Boolean: whether this is for a preview
+	 * @param $section Boolean: whether this is for a section edit
+	 * @return String: HTML output
+	 */
+	public static function formatDistantTemplates( $templates, $preview = false, $section = false ) {
+		wfProfileIn( __METHOD__ );
+
+		$outText = '';
+		if ( count( $templates ) > 0 ) {
+
+			# Construct the HTML
+			$outText = '<div class="mw-templatesUsedExplanation">';
+			if ( $preview ) {
+				$outText .= wfMsgExt( 'distanttemplatesusedpreview', array( 'parse' ), count( $templates ) );
+			} elseif ( $section ) {
+				$outText .= wfMsgExt( 'distanttemplatesusedsection', array( 'parse' ), count( $templates ) );
+			} else {
+				$outText .= wfMsgExt( 'distanttemplatesused', array( 'parse' ), count( $templates ) );
+			}
+			$outText .= "</div><ul>\n";
+
+			usort( $templates, array( 'Title', 'compare' ) );
+			foreach ( $templates as $titleObj ) {
+				$outText .= '<li>' . self::link( $titleObj ) . '</li>';
+			}
+			$outText .= '</ul>';
+		}
+		wfProfileOut( __METHOD__  );
+		return $outText;
+	}
+
 	/**
 	 * Returns HTML for the "hidden categories on this page" list.
 	 *
diff --git a/includes/LinksUpdate.php b/includes/LinksUpdate.php
index 3252fb655f..da77601319 100644
--- a/includes/LinksUpdate.php
+++ b/includes/LinksUpdate.php
@@ -29,6 +29,7 @@ class LinksUpdate {
 		$mLinks,         //!< Map of title strings to IDs for the links in the document
 		$mImages,        //!< DB keys of the images used, in the array key only
 		$mTemplates,     //!< Map of title strings to IDs for the template references, including broken ones
+		$mDistantTemplates,//!< Map of title strings to IDs for the distant template references, including broken ones
 		$mExternals,     //!< URLs of external links, array key only
 		$mCategories,    //!< Map of category names to sort keys
 		$mInterlangs,    //!< Map of language codes to titles
@@ -66,6 +67,7 @@ class LinksUpdate {
 		$this->mLinks = $parserOutput->getLinks();
 		$this->mImages = $parserOutput->getImages();
 		$this->mTemplates = $parserOutput->getTemplates();
+		$this->mDistantTemplates = $parserOutput->getDistantTemplates();
 		$this->mExternals = $parserOutput->getExternalLinks();
 		$this->mCategories = $parserOutput->getCategories();
 		$this->mProperties = $parserOutput->getProperties();
@@ -152,6 +154,15 @@ class LinksUpdate {
 		$this->incrTableUpdate( 'templatelinks', 'tl', $this->getTemplateDeletions( $existing ),
 			$this->getTemplateInsertions( $existing ) );
 
+		# Distant template links
+		global $wgGlobalDB;
+		if ( $wgGlobalDB ) {
+			$existing = $this->getDistantExistingTemplates();
+			$this->incrSharedTableUpdate( 'globaltemplatelinks', 'gtl',
+				$this->getDistantTemplateDeletions( $existing ),
+				$this->getDistantTemplateInsertions( $existing ) );
+		}
+
 		# Category links
 		$existing = $this->getExistingCategories();
 
@@ -367,11 +378,55 @@ class LinksUpdate {
 		if ( $where ) {
 			$this->mDb->delete( $table, $where, __METHOD__ );
 		}
+		if ( isset( $insertions['globaltemplatelinks'] ) ) {
+			$this->mDb->insert( 'globaltemplatelinks', $insertions['globaltemplatelinks'], __METHOD__, 'IGNORE' );
+			unset( $insertions['globaltemplatelinks'] );
+		}
+		if ( isset( $insertions['globalnamespaces'] ) ) {
+			$this->mDb->insert( 'globalnamespaces', $insertions['globalnamespaces'], __METHOD__, 'IGNORE' );
+			unset( $insertions['globalnamespaces'] );
+		}
+		if ( isset( $insertions['globalinterwiki'] ) ) {
+			$this->mDb->insert( 'globalinterwiki', $insertions['globalinterwiki'], __METHOD__, 'IGNORE' );
+			unset( $insertions['globalinterwiki'] );
+		}
 		if ( count( $insertions ) ) {
 			$this->mDb->insert( $table, $insertions, __METHOD__, 'IGNORE' );
 		}
 	}
 
+	/**
+	 * Update a shared table by doing a delete query then an insert query
+	 * @private
+	 */
+	function incrSharedTableUpdate( $table, $prefix, $deletions, $insertions ) {
+
+		global $wgWikiID;
+		global $wgGlobalDB;
+
+		if ( $wgGlobalDB ) {
+			$dbw = wfGetDB( DB_MASTER, array(), $wgGlobalDB );
+			$where = array( "{$prefix}_from_wiki" => $wgWikiID,
+							"{$prefix}_from_page" => $this->mId
+					);
+			$baseKey = "{$prefix}_to_wiki";
+			$middleKey = "{$prefix}_to_namespace";
+
+			$clause = $dbw->makeWhereFrom3d( $deletions, $baseKey, $middleKey, "{$prefix}_to_title" );
+			if ( $clause ) {
+				$where[] = $clause;
+			} else {
+				$where = false;
+			}
+
+			if ( $where ) {
+				$dbw->delete( $table, $where, __METHOD__ );
+			}
+			if ( count( $insertions ) ) {
+				$dbw->insert( $table, $insertions, __METHOD__, 'IGNORE' );
+			}
+		}
+	}
 
 	/**
 	 * Get an array of pagelinks insertions for passing to the DB
@@ -414,6 +469,45 @@ class LinksUpdate {
 		return $arr;
 	}
 
+	/**
+	 * Get an array of distant template insertions. Like getLinkInsertions()
+	 * @private
+	 */
+	function getDistantTemplateInsertions( $existing = array() ) {
+		global $wgWikiID;
+		$arr = array();
+		foreach( $this->mDistantTemplates as $wikiid => $templatesToNS ) {
+			foreach( $templatesToNS as $ns => $dbkeys ) {
+				$diffs = isset( $existing[$wikiid] ) && isset( $existing[$wikiid][$ns] )
+						? array_diff_key( $dbkeys, $existing[$wikiid][$ns] )
+						: $dbkeys;
+				$interwiki = Interwiki::fetch( $wikiid );
+				$wikiid = $interwiki->getWikiID();
+				foreach ( $diffs as $dbk => $id ) {
+					$arr['globaltemplatelinks'][] = array(
+						'gtl_from_wiki'      => $wgWikiID,
+						'gtl_from_page'      => $this->mId,
+						'gtl_from_namespace' => $this->mTitle->getNamespace(),
+						'gtl_from_title'     => $this->mTitle->getText(),
+						'gtl_to_wiki'        => $wikiid,
+						'gtl_to_namespace'   => $ns,
+						'gtl_to_title'       => $dbk
+					);
+					$arr['globalinterwiki'][] = array(
+						'giw_wikiid'		 => $wikiid,
+						'giw_prefix'		 => $prefix // FIXME: $prefix ix undefined
+					);
+					$arr['globalnamespaces'][] = array(
+						'gn_wiki'			 => wfWikiID( ),
+						'gn_namespace'   	 => $this->mTitle->getNamespace(),
+						'gn_namespacetext' 	 => $this->mTitle->getNsText(),
+					);
+				}
+			}
+		}
+		return $arr;
+	}
+
 	/**
 	 * Get an array of image insertions
 	 * Skips the names specified in $existing
@@ -580,6 +674,30 @@ class LinksUpdate {
 		return $del;
 	}
 
+	/**
+	 * Given an array of existing templates, returns those templates which are not in $this
+	 * and thus should be deleted.
+	 * @private
+	 */
+	function getDistantTemplateDeletions( $existing ) {
+		$del = array();
+		foreach ( $existing as $wikiid => $templatesForNS ) {
+			if ( isset( $this->mDistantTemplates[$wikiid] ) ) {
+				$del[$wikiid] = array_diff_key( $existing[$wikiid], $this->mDistantTemplates[$wikiid] );
+			} else {
+				$del[$wikiid] = $existing[$wikiid];
+			}
+			foreach ( $templatesForNS as $ns => $dbkeys ) {
+				if ( isset( $this->mDistantTemplates[$wikiid][$ns] ) ) {
+					$del[$wikiid][$ns] = array_diff_key( $existing[$wikiid][$ns], $this->mDistantTemplates[$wikiid][$ns] );
+				} else {
+					$del[$wikiid][$ns] = $existing[$wikiid][$ns];
+				}
+			}
+		}
+		return $del;
+	}
+
 	/**
 	 * Given an array of existing images, returns those images which are not in $this
 	 * and thus should be deleted.
@@ -675,6 +793,33 @@ class LinksUpdate {
 		return $arr;
 	}
 
+	/**
+	 * Get an array of existing distant templates, as a 3-D array
+	 * @private
+	 */
+	function getDistantExistingTemplates() {
+		global $wgWikiID;
+		global $wgGlobalDB;
+
+		$arr = array();
+		if ( $wgGlobalDB ) {
+			$dbr = wfGetDB( DB_SLAVE, array(), $wgGlobalDB );
+			$res = $dbr->select( 'globaltemplatelinks', array( 'gtl_to_wiki', 'gtl_to_namespace', 'gtl_to_title' ),
+				array( 'gtl_from_wiki' => $wgWikiID, 'gtl_from_page' => $this->mId ), __METHOD__, $this->mOptions );
+			while ( $row = $dbr->fetchObject( $res ) ) {
+				if ( !isset( $arr[$row->gtl_to_wiki] ) ) {
+					$arr[$row->gtl_to_wiki] = array();
+				}
+				if ( !isset( $arr[$row->gtl_to_wiki][$row->gtl_to_namespace] ) ) {
+					$arr[$row->gtl_to_wiki][$row->gtl_to_namespace] = array();
+				}
+				$arr[$row->gtl_to_wiki][$row->gtl_to_namespace][$row->gtl_to_title] = 1;
+			}
+			$dbr->freeResult( $res );
+		}
+		return $arr;
+	}
+
 	/**
 	 * Get an array of existing images, image names in the keys
 	 * @private
diff --git a/includes/OutputPage.php b/includes/OutputPage.php
index a80e3156b1..4d06feb4d3 100644
--- a/includes/OutputPage.php
+++ b/includes/OutputPage.php
@@ -2048,6 +2048,9 @@ class OutputPage extends ContextSource {
 	 * @param $action    String: action that was denied or null if unknown
 	 */
 	public function readOnlyPage( $source = null, $protected = false, $reasons = array(), $action = null ) {
+		global $wgUser, $wgEnableInterwikiTranscluding, $wgEnableInterwikiTemplatesTracking;
+		$skin = $wgUser->getSkin();
+
 		$this->setRobotPolicy( 'noindex,nofollow' );
 		$this->setArticleRelated( false );
 
@@ -2093,6 +2096,12 @@ class OutputPage extends ContextSource {
 $templates
 </div>
 " );
+			if ( $wgEnableInterwikiTranscluding && $wgEnableInterwikiTemplatesTracking ) {
+				$this->addHTML( "<div class='distantTemplatesUsed'>
+{$skin->formatDistantTemplates( $article->getUsedDistantTemplates( ) )}
+</div>
+" );
+		}
 		}
 
 		# If the title doesn't exist, it's fairly pointless to print a return
diff --git a/includes/Revision.php b/includes/Revision.php
index f93108017b..243c9c06a0 100644
--- a/includes/Revision.php
+++ b/includes/Revision.php
@@ -165,6 +165,30 @@ class Revision {
 		return Revision::loadFromConds( $db, $conds );
 	}
 
+	/**
+	 * Stores the origin wiki of a revision in case it is a foreign wiki
+	 */
+	function setWikiID( $wikiID ) {
+		$this->mWikiID = $wikiID;
+	}
+
+	/**
+	 * Load the current revision of a given page of a foreign wiki.
+	 * The WikiID is stored for further use, such as loadText() and getTimestampFromId()
+	 */
+	public static function loadFromTitleForeignWiki( $wikiID, $title ) {
+		$dbr = wfGetDB( DB_SLAVE, array(), $wikiID );
+
+		$revision = self::loadFromTitle( $dbr, $title );
+
+		if( $revision ) {
+			$revision->setWikiID( $wikiID );
+		}
+
+		return $revision;
+
+	}
+
 	/**
 	 * Load either the current, or a specified, revision
 	 * that's attached to a given page. If not attached
@@ -402,6 +426,7 @@ class Revision {
 			throw new MWException( 'Revision constructor passed invalid row format.' );
 		}
 		$this->mUnpatrolled = null;
+		$this->mWikiID = false;
 	}
 
 	/**
@@ -449,7 +474,8 @@ class Revision {
 		if( isset( $this->mTitle ) ) {
 			return $this->mTitle;
 		}
-		$dbr = wfGetDB( DB_SLAVE );
+		$dbr = wfGetDB( DB_SLAVE, array(), $this->mWikiID );
+
 		$row = $dbr->selectRow(
 			array( 'page', 'revision' ),
 			array( 'page_namespace', 'page_title' ),
@@ -588,7 +614,7 @@ class Revision {
 		if( $this->mUnpatrolled !== null ) {
 			return $this->mUnpatrolled;
 		}
-		$dbr = wfGetDB( DB_SLAVE );
+		$dbr = wfGetDB( DB_SLAVE, array(), $this->mWikiID );
 		$this->mUnpatrolled = $dbr->selectField( 'recentchanges',
 			'rc_id',
 			array( // Add redundant user,timestamp condition so we can use the existing index
@@ -924,7 +950,11 @@ class Revision {
 		// Caching may be beneficial for massive use of external storage
 		global $wgRevisionCacheExpiry, $wgMemc;
 		$textId = $this->getTextId();
+		if( isset( $this->mWikiID ) && $this->mWikiID !== false ) {
+			$key = wfForeignMemcKey( $this->mWikiID, null, 'revisiontext', 'textid', $textId );
+		} else {
 		$key = wfMemcKey( 'revisiontext', 'textid', $textId );
+		}
 		if( $wgRevisionCacheExpiry ) {
 			$text = $wgMemc->get( $key );
 			if( is_string( $text ) ) {
@@ -944,7 +974,7 @@ class Revision {
 
 		if( !$row ) {
 			// Text data is immutable; check slaves first.
-			$dbr = wfGetDB( DB_SLAVE );
+			$dbr = wfGetDB( DB_SLAVE, array(), $this->mWikiID );
 			$row = $dbr->selectRow( 'text',
 				array( 'old_text', 'old_flags' ),
 				array( 'old_id' => $this->getTextId() ),
@@ -953,7 +983,7 @@ class Revision {
 
 		if( !$row && wfGetLB()->getServerCount() > 1 ) {
 			// Possible slave lag!
-			$dbw = wfGetDB( DB_MASTER );
+			$dbw = wfGetDB( DB_MASTER, array(), $this->mWikiID );
 			$row = $dbw->selectRow( 'text',
 				array( 'old_text', 'old_flags' ),
 				array( 'old_id' => $this->getTextId() ),
@@ -1064,7 +1094,8 @@ class Revision {
 	 * @return String
 	 */
 	static function getTimestampFromId( $title, $id ) {
-		$dbr = wfGetDB( DB_SLAVE );
+		$wikiId = wfWikiID();
+		$dbr = wfGetDB( DB_SLAVE, array(), $wikiId );
 		// Casting fix for DB2
 		if ( $id == '' ) {
 			$id = 0;
@@ -1074,7 +1105,7 @@ class Revision {
 		$timestamp = $dbr->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
 		if ( $timestamp === false && wfGetLB()->getServerCount() > 1 ) {
 			# Not in slave, try master
-			$dbw = wfGetDB( DB_MASTER );
+			$dbw = wfGetDB( DB_MASTER, array(), $wikiId );
 			$timestamp = $dbw->selectField( 'revision', 'rev_timestamp', $conds, __METHOD__ );
 		}
 		return wfTimestamp( TS_MW, $timestamp );
diff --git a/includes/SpecialPageFactory.php b/includes/SpecialPageFactory.php
index 2b8e173f07..40a981d14c 100644
--- a/includes/SpecialPageFactory.php
+++ b/includes/SpecialPageFactory.php
@@ -126,6 +126,8 @@ class SpecialPageFactory {
 		// Page tools
 		'ComparePages'              => 'SpecialComparePages',
 		'Export'                    => 'SpecialExport',
+		'GlobalFileUsage'           => 'SpecialGlobalFileUsage',
+		'GlobalTemplateUsage'       => 'SpecialGlobalTemplateUsage',
 		'Import'                    => 'SpecialImport',
 		'Undelete'                  => 'SpecialUndelete',
 		'Whatlinkshere'             => 'SpecialWhatlinkshere',
diff --git a/includes/Title.php b/includes/Title.php
index 4f61897f0a..f2099950f2 100644
--- a/includes/Title.php
+++ b/includes/Title.php
@@ -757,6 +757,20 @@ class Title {
 		return $this->mPrefixedText;
 	}
 
+	/**
+	 * Return the prefixed title with spaces _without_ the interwiki prefix
+	 * 
+	 * @return \type{\string} the title, prefixed by the namespace but not by the interwiki prefix, with spaces
+	 */
+	public function getSemiPrefixedText() {
+		if ( !isset( $this->mSemiPrefixedText ) ){
+			$s = ( $this->mNamespace === NS_MAIN ? '' : $this->getNsText() . ':' ) . $this->mTextform;
+			$s = str_replace( '_', ' ', $s );
+			$this->mSemiPrefixedText = $s;
+		}
+		return $this->mSemiPrefixedText; 
+	}
+
 	/**
 	 * Get the prefixed title with spaces, plus any fragment
 	 * (part beginning with '#')
@@ -1009,8 +1023,12 @@ class Title {
 	 * @return String the URL
 	 */
 	public function getInternalURL( $query = '', $variant = false ) {
-		global $wgInternalServer, $wgServer;
-		$server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
+		if ( $this->isExternal( ) ) {
+			$server = '';
+		} else {
+			global $wgInternalServer, $wgServer;
+			$server = $wgInternalServer !== false ? $wgInternalServer : $wgServer;
+		}
 		$url = wfExpandUrl( $server . $this->getLocalURL( $query, $variant ), PROTO_HTTP );
 		wfRunHooks( 'GetInternalURL', array( &$this, &$url, $query ) );
 		return $url;
@@ -2836,6 +2854,10 @@ class Title {
 		$this->mFragment = str_replace( '_', ' ', substr( $fragment, 1 ) );
 	}
 
+	public function setInterwiki( $interwiki ) {
+		$this->mInterwiki = $interwiki;
+	}
+
 	/**
 	 * Get a Title object associated with the talk page of this article
 	 *
@@ -3140,6 +3162,8 @@ class Title {
 	 * @return Mixed true on success, getUserPermissionsErrors()-like array on failure
 	 */
 	public function moveTo( &$nt, $auth = true, $reason = '', $createRedirect = true ) {
+		global $wgContLang, $wgEnableInterwikiTemplatesTracking, $wgGlobalDatabase;
+
 		$err = $this->isValidMoveOperation( $nt, $auth, $reason );
 		if ( is_array( $err ) ) {
 			return $err;
@@ -3196,6 +3220,15 @@ class Title {
 			);
 		}
 
+		if ( $wgEnableInterwikiTemplatesTracking && $wgGlobalDatabase ) {
+			$dbw2 = wfGetDB( DB_MASTER, array(), $wgGlobalDatabase );
+			$dbw2->update( 'globaltemplatelinks',
+						array(  'gtl_from_namespace' => $nt->getNamespace(),
+								'gtl_from_title' => $nt->getText() ),
+						array ( 'gtl_from_page' => $pageid ),
+						__METHOD__ );
+		}
+
 		if ( $protected ) {
 			# Protect the redirect title as the title used to be...
 			$dbw->insertSelect( 'page_restrictions', 'page_restrictions',
@@ -3289,8 +3322,8 @@ class Title {
 	 * @param $createRedirect Bool Whether to leave a redirect at the old title.  Ignored
 	 *   if the user doesn't have the suppressredirect right
 	 */
-	private function moveToInternal( &$nt, $reason = '', $createRedirect = true ) {
-		global $wgUser, $wgContLang;
+	private function moveOverExistingRedirect( &$nt, $reason = '', $createRedirect = true ) {
+		global $wgUseSquid, $wgUser, $wgContLang, $wgEnableInterwikiTemplatesTracking, $wgGlobalDatabase;
 
 		$moveOverRedirect = $nt->exists();
 
@@ -3340,6 +3373,14 @@ class Title {
 				array( 'rc_timestamp' => $rcts, 'rc_namespace' => $newns, 'rc_title' => $newdbk, 'rc_new' => 1 ),
 				__METHOD__
 			);
+			
+			 if ( $wgEnableInterwikiTemplatesTracking && $wgGlobalDatabase ) {
+				$dbw2 = wfGetDB( DB_MASTER, array(), $wgGlobalDatabase );
+				$dbw2->delete( 'globaltemplatelinks',
+							array(  'gtl_from_wiki' => wfGetID(),
+									'gtl_from_page' => $newid ),
+							__METHOD__ );
+		}
 		}
 
 		# Save a null revision in the page's history notifying of the move
diff --git a/includes/WikiPage.php b/includes/WikiPage.php
index dbff4d8521..047dd20236 100644
--- a/includes/WikiPage.php
+++ b/includes/WikiPage.php
@@ -1604,7 +1604,7 @@ class WikiPage extends Page {
 	public function doDeleteArticle(
 		$reason, $suppress = false, $id = 0, $commit = true, &$error = '', User $user = null
 	) {
-		global $wgDeferredUpdateList, $wgUseTrackbacks, $wgUser;
+		global $wgDeferredUpdateList, $wgUseTrackbacks, $wgEnableInterwikiTemplatesTracking, $wgGlobalDatabase, $wgUser;
 		$user = is_null( $user ) ? $wgUser : $user;
 
 		wfDebug( __METHOD__ . "\n" );
@@ -1709,6 +1709,14 @@ class WikiPage extends Page {
 			$dbw->delete( 'iwlinks', array( 'iwl_from' => $id ), __METHOD__ );
 			$dbw->delete( 'redirect', array( 'rd_from' => $id ), __METHOD__ );
 			$dbw->delete( 'page_props', array( 'pp_page' => $id ), __METHOD__ );
+
+			if ( $wgEnableInterwikiTemplatesTracking && $wgGlobalDatabase ) {
+				$dbw2 = wfGetDB( DB_MASTER, array(), $wgGlobalDatabase );
+				$dbw2->delete( 'globaltemplatelinks',
+							array(  'gtl_from_wiki' => wfGetID(),
+									'gtl_from_page' => $id )
+							);
+		}
 		}
 
 		# If using cleanup triggers, we can skip some manual deletes
@@ -2213,6 +2221,8 @@ class WikiPage extends Page {
 	 * @param $title Title object
 	 */
 	public static function onArticleCreate( $title ) {
+		global $wgDeferredUpdateList;
+
 		# Update existence markers on article/talk tabs...
 		if ( $title->isTalkPage() ) {
 			$other = $title->getSubjectPage();
@@ -2226,6 +2236,9 @@ class WikiPage extends Page {
 		$title->touchLinks();
 		$title->purgeSquid();
 		$title->deleteTitleProtection();
+
+		# Invalidate caches of distant articles which transclude this page
+		$wgDeferredUpdateList[] = new HTMLCacheUpdate( $title, 'globaltemplatelinks' );
 	}
 
 	/**
@@ -2234,6 +2247,8 @@ class WikiPage extends Page {
 	 * @param $title Title
 	 */
 	public static function onArticleDelete( $title ) {
+		global $wgMessageCache, $wgDeferredUpdateList;
+
 		# Update existence markers on article/talk tabs...
 		if ( $title->isTalkPage() ) {
 			$other = $title->getSubjectPage();
@@ -2269,6 +2284,9 @@ class WikiPage extends Page {
 
 		# Image redirects
 		RepoGroup::singleton()->getLocalRepo()->invalidateImageRedirect( $title );
+
+		# Invalidate caches of distant articles which transclude this page
+		$wgDeferredUpdateList[] = new HTMLCacheUpdate( $title, 'globaltemplatelinks' );
 	}
 
 	/**
@@ -2283,6 +2301,9 @@ class WikiPage extends Page {
 		// Invalidate caches of articles which include this page
 		$wgDeferredUpdateList[] = new HTMLCacheUpdate( $title, 'templatelinks' );
 
+		// Invalidate caches of distant articles which transclude this page
+		$wgDeferredUpdateList[] = new HTMLCacheUpdate( $title, 'globaltemplatelinks' );
+
 		// Invalidate the caches of all pages which redirect here
 		$wgDeferredUpdateList[] = new HTMLCacheUpdate( $title, 'redirect' );
 
@@ -2324,6 +2345,40 @@ class WikiPage extends Page {
 		return $result;
 	}
 
+	/**
+	 * Return a list of distant templates used by this article.
+	 * Uses the globaltemplatelinks table
+	 *
+	 * @return Array of Title objects
+	 */
+	public function getUsedDistantTemplates() {
+		global $wgGlobalDatabase;
+
+		$result = array();
+
+		if ( $wgGlobalDatabase ) {
+			$id = $this->mTitle->getArticleID();
+
+			if ( $id == 0 ) {
+				return array();
+			}
+
+			$dbr = wfGetDB( DB_SLAVE, array(), $wgGlobalDatabase );
+			$res = $dbr->select( 'globaltemplatelinks',
+				array( 'gtl_to_prefix', 'gtl_to_namespace', 'gtl_to_title' ),
+				array( 'gtl_from_wiki' => wfWikiID( ), 'gtl_from_page' => $id ),
+				__METHOD__ );
+
+			if ( $res !== false ) {
+				foreach ( $res as $row ) {
+					$result[] = Title::makeTitle( $row->gtl_to_namespace, $row->gtl_to_title, null, $row->gtl_to_prefix );
+				}
+			}
+		}
+
+		return $result;
+	}
+
 	/**
 	 * Returns a list of hidden categories this page is a member of.
 	 * Uses the page_props and categorylinks tables.
diff --git a/includes/cache/HTMLCacheUpdate.php b/includes/cache/HTMLCacheUpdate.php
index d542800db2..433e91cb5a 100644
--- a/includes/cache/HTMLCacheUpdate.php
+++ b/includes/cache/HTMLCacheUpdate.php
@@ -51,6 +51,16 @@ class HTMLCacheUpdate
 			return;
 		}
 
+		if ( $this->mTable === 'globaltemplatelinks' ) {
+			global $wgEnableInterwikiTemplatesTracking;
+			
+			if ( $wgEnableInterwikiTemplatesTracking ) {
+				$distantPageArray = $this->mCache->getDistantTemplateLinks( 'globaltemplatelinks' );
+				$this->invalidateDistantTitles( $distantPageArray );
+			}
+			return;
+		}
+
 		# Get an estimate of the number of rows from the BacklinkCache
 		$numRows = $this->mCache->getNumLinks( $this->mTable );
 		if ( $numRows > $this->mRowsPerJob * 2 ) {
@@ -68,6 +78,7 @@ class HTMLCacheUpdate
 				$this->invalidateTitles( $titleArray );
 			}
 		}
+		wfRunHooks( 'HTMLCacheUpdate::doUpdate', array($this->mTitle) );
 	}
 
 	/**
@@ -198,6 +209,44 @@ class HTMLCacheUpdate
 		}
 	}
 
+	/**
+	 * Invalidate an array of distant pages, given the wiki ID and page ID of those pages
+	 */
+	protected function invalidateDistantTitles( $distantPageArray ) {
+		global $wgUseFileCache, $wgUseSquid, $wgLocalInterwiki;
+		
+		$pagesByWiki = array();
+		$titleArray = array();
+		# Sort by WikiID in $pagesByWiki
+	 	# Create the distant titles for Squid in $titleArray
+		foreach ( $distantPageArray as $row ) {
+			$wikiid = $row->gtl_from_wiki;
+			if( !isset( $pagesByWiki[$wikiid] ) ) {
+				$pagesByWiki[$wikiid] = array();
+}
+			$pagesByWiki[$wikiid][] = $row->gtl_from_page;
+			$titleArray[] = Title::makeTitle( $row->gtl_from_namespace, $row->gtl_from_title, '', $row->gil_interwiki );
+		}
+
+		foreach ( $pagesByWiki as $wikiid => $pages ) {
+			$dbw = wfGetDB( DB_MASTER, array( ), $wikiid );
+			$timestamp = $dbw->timestamp();
+			$batches = array_chunk( $pages, $this->mRowsPerQuery );
+			foreach ( $batches as $batch ) {
+				$dbw->update( 'page',
+					array( 'page_touched' => $timestamp ),
+					array( 'page_id IN (' . $dbw->makeList( $batch ) . ')' ),
+					__METHOD__
+				);
+			}
+		}
+		
+		# Update squid
+		if ( $wgUseSquid ) {
+			$u = SquidUpdate::newFromTitles( $titleArray );
+			$u->doUpdate();
+		}
+	}
 }
 
 /**
diff --git a/includes/db/Database.php b/includes/db/Database.php
index be06053e94..279948fb37 100644
--- a/includes/db/Database.php
+++ b/includes/db/Database.php
@@ -1819,6 +1819,39 @@ abstract class DatabaseBase implements DatabaseType {
 		}
 	}
 
+	/**
+	 * Build a partial where clause from a 3-d array
+	 * The keys on each level may be either integers or strings.
+	 *
+	 * @param $data Array: organized as 3-d array(baseKeyVal => array(middleKeyVal => array(subKeyVal => <ignored>, ...), ...), ...)
+	 * @param $baseKey String: field name to match the base-level keys to (eg 'gtl_to_prefix')
+	 * @param $middleKey String: field name to match the middle-level keys to (eg 'gtl_to_namespace')
+	 * @param $subKey String: field name to match the sub-level keys to (eg 'gtl_to_title')
+	 * @return Mixed: string SQL fragment, or false if no items in array.
+	 */
+	function makeWhereFrom3d( $data, $baseKey, $middleKey, $subKey ) {
+		$conds = array();
+		foreach ( $data as $base => $subdata ) {
+			foreach ( $subdata as $middle => $sub ) {
+				if ( count( $sub ) ) {
+					$conds[] = $this->makeList(
+						array( $baseKey => $base,
+							$middleKey => $middle,
+							$subKey => array_keys( $sub ) ),
+						LIST_AND
+					);
+				}
+			}
+		}
+
+		if ( $conds ) {
+			return $this->makeList( $conds, LIST_OR );
+		} else {
+			// Nothing to search for...
+			return false;
+		}
+	}
+
 	/**
 	 * Bitwise operations
 	 */
diff --git a/includes/installer/MysqlUpdater.php b/includes/installer/MysqlUpdater.php
index e2a6926d9f..29d2673178 100644
--- a/includes/installer/MysqlUpdater.php
+++ b/includes/installer/MysqlUpdater.php
@@ -185,6 +185,9 @@ class MysqlUpdater extends DatabaseUpdater {
 			// 1.19
 			array( 'addTable', 'config',                            'patch-config.sql' ),
 			array( 'addIndex', 'logging',       'type_action',      'patch-logging-type-action-index.sql'),
+			array( 'addTable', 'globaltemplatelinks', 'patch-globaltemplatelinks.sql' ),
+			array( 'addTable', 'globalnamespaces', 'patch-globalnamespaces.sql' ),
+			array( 'addTable', 'globalinterwiki', 'patch-globalinterwiki.sql' ),
 		);
 	}
 
diff --git a/includes/installer/SqliteUpdater.php b/includes/installer/SqliteUpdater.php
index 2e81f6cbe6..05273853b9 100644
--- a/includes/installer/SqliteUpdater.php
+++ b/includes/installer/SqliteUpdater.php
@@ -63,6 +63,11 @@ class SqliteUpdater extends DatabaseUpdater {
 			// 1.19
 			array( 'addTable', 'config',                            'patch-config.sql' ),
 			array( 'addIndex', 'logging',       'type_action',      'patch-logging-type-action-index.sql')
+
+			// 1.19
+			array( 'addTable', 'globaltemplatelinks', 'patch-globaltemplatelinks.sql' ),
+			array( 'addTable', 'globalnamespaces', 'patch-globalnamespaces.sql' ),
+			array( 'addTable', 'globalinterwiki', 'patch-globalinterwiki.sql' ),
 		);
 	}
 
diff --git a/includes/interwiki/Interwiki.php b/includes/interwiki/Interwiki.php
index d1592c0bf0..ac9bee7657 100644
--- a/includes/interwiki/Interwiki.php
+++ b/includes/interwiki/Interwiki.php
@@ -9,6 +9,7 @@
  * All information is loaded on creation when called by Interwiki::fetch( $prefix ).
  * All work is done on slave, because this should *never* change (except during
  * schema updates etc, which aren't wiki-related)
+ * This class also contains the functions that allow interwiki templates transclusion.
  */
 class Interwiki {
 
@@ -168,6 +169,7 @@ class Interwiki {
 			$mc = array(
 				'iw_url' => $iw->mURL,
 				'iw_api' => $iw->mAPI,
+				'iw_wikiid' => $iw->mWikiID,
 				'iw_local' => $iw->mLocal,
 				'iw_trans' => $iw->mTrans
 			);
@@ -190,6 +192,7 @@ class Interwiki {
 			$iw->mURL = $mc['iw_url'];
 			$iw->mLocal = isset( $mc['iw_local'] ) ? $mc['iw_local'] : 0;
 			$iw->mTrans = isset( $mc['iw_trans'] ) ? $mc['iw_trans'] : 0;
+			$iw->mAPI = isset( $mc['iw_api'] ) ? $mc['iw_api'] : 
 			$iw->mAPI = isset( $mc['iw_api'] ) ? $mc['iw_api'] : '';
 			$iw->mWikiID = isset( $mc['iw_wikiid'] ) ? $mc['iw_wikiid'] : '';
 
@@ -384,4 +387,166 @@ class Interwiki {
 		$msg = wfMessage( 'interwiki-desc-' . $this->mPrefix )->inContentLanguage();
 		return !$msg->exists() ? '' : $msg;
 	}
+	
+
+	/**
+	 * Transclude an interwiki link.
+	 */
+	public static function interwikiTransclude( $title ) {
+			
+		// If we have a wikiID, we will use it to get an access to the remote database
+		// if not, we will use the API URL to retrieve the data through a HTTP Get
+		
+		$wikiID = $title->getTransWikiID( );
+		$transAPI = $title->getTransAPI( );
+		
+		if ( $wikiID !== '') {
+		
+			$finalText = self::fetchTemplateFromDB( $wikiID, $title );
+			return $finalText;
+
+		} else if( $transAPI !== '' ) {
+			
+			$interwiki = $title->getInterwiki( );
+			$fullTitle = $title->getSemiPrefixedText( );
+			
+			$finalText = self::fetchTemplateFromAPI( $interwiki, $transAPI, $fullTitle );
+			
+			return $finalText;
+			
+}
+		return false;
+	}
+	
+	/**
+	 * Retrieve the wikitext of a distant page accessing the foreign DB
+	 */
+	public static function fetchTemplateFromDB ( $wikiID, $title ) {
+		
+		$revision = Revision::loadFromTitleForeignWiki( $wikiID, $title );
+		
+		if ( $revision ) {
+			$text = $revision->getText();
+			return $text;
+		}
+				
+		return false;
+	}
+	
+	/**
+	 * Retrieve the wikitext of a distant page using the API of the foreign wiki
+	 */
+	public static function fetchTemplateFromAPI( $interwiki, $transAPI, $fullTitle ) {
+		global $wgMemc, $wgTranscludeCacheExpiry;
+		
+		$key = wfMemcKey( 'iwtransclustiontext', 'textid', $interwiki, $fullTitle );
+		$text = $wgMemc->get( $key );
+		if( is_array ( $text ) &&
+				isset ( $text['missing'] ) &&
+				$text['missing'] === true ) {
+			return false;
+		} else if ( $text ) {
+			return $text;
+		}
+		
+		$url = wfAppendQuery(
+			$transAPI,
+			array(	'action' => 'query',
+					'titles' => $fullTitle,
+					'prop' => 'revisions',
+					'rvprop' => 'content',
+					'format' => 'json'
+			)
+		);
+		
+		$get = Http::get( $url );
+		$content = FormatJson::decode( $get, true );
+			
+		if ( isset ( $content['query'] ) &&
+				isset ( $content['query']['pages'] ) ) {
+			$page = array_pop( $content['query']['pages'] );
+			if ( $page && isset( $page['revisions'][0]['*'] ) ) {
+				$text = $page['revisions'][0]['*'];
+				$wgMemc->set( $key, $text, $wgTranscludeCacheExpiry );
+
+				// When we cache a template, we also retrieve and cache its subtemplates
+				$subtemplates = self::getSubtemplatesListFromAPI( $interwiki, $transAPI, $fullTitle );
+				self::cacheTemplatesFromAPI( $interwiki, $transAPI, $subtemplates );
+				
+				return $text;
+			} else {
+				$wgMemc->set( $key, array ( 'missing' => true ), $wgTranscludeCacheExpiry );
+			}
+		}
+		return false;
+	}	
+
+	public static function getSubtemplatesListFromAPI ( $interwiki, $transAPI, $title ) {
+		$url = wfAppendQuery( $transAPI,
+			array( 'action' => 'query',
+			'titles' => $title,
+			'prop' => 'templates',
+			'format' => 'json'
+			)
+		);
+			
+		$get = Http::get( $url );
+		$myArray = FormatJson::decode($get, true);
+
+		$templates = array( );
+		if ( ! empty( $myArray['query'] )) {
+			if ( ! empty( $myArray['query']['pages'] )) {
+				$templates = array_pop( $myArray['query']['pages'] );
+				if ( ! empty( $templates['templates'] )) {
+					$templates = $templates['templates'];
+				}
+			}
+			return $templates;
+		}
+	}
+
+	public static function cacheTemplatesFromAPI( $interwiki, $transAPI, $titles ){
+		global $wgMemc, $wgTranscludeCacheExpiry;
+		
+		$outdatedTitles = array( );
+		
+		foreach( $titles as $title ){
+			if ( isset ( $title['title'] ) ) {
+				$key = wfMemcKey( 'iwtransclustiontext', 'textid', $interwiki, $title['title'] );
+				$text = $wgMemc->get( $key );
+				if( !$text ){
+					$outdatedTitles[] = $title['title'];
+				}
+			}			
+		}
+		
+		$batches = array_chunk( $outdatedTitles, 50 );
+		
+		foreach( $batches as $batch ){
+			$url = wfAppendQuery(
+				$transAPI,
+				array(	'action' => 'query',
+						'titles' => implode( '|', $batch ),
+						'prop' => 'revisions',
+						'rvprop' => 'content',
+						'format' => 'json'
+				)
+			);
+			$get = Http::get( $url );
+			$content = FormatJson::decode( $get, true );
+				
+			if ( isset ( $content['query'] ) &&
+					isset ( $content['query']['pages'] ) ) {
+				foreach( $content['query']['pages'] as $page ) {
+					$key = wfMemcKey( 'iwtransclustiontext', 'textid', $interwiki, $page['title'] );
+					if ( isset ( $page['revisions'][0]['*'] ) ) {
+						$text = $page['revisions'][0]['*'];
+					} else {
+						$text = array ( 'missing' => true );
+					}
+					$wgMemc->set( $key, $text, $wgTranscludeCacheExpiry );	
+				}
+			}
+		}
+	}
 }
diff --git a/includes/parser/Parser.php b/includes/parser/Parser.php
index 3233fbf6b7..77749726ae 100644
--- a/includes/parser/Parser.php
+++ b/includes/parser/Parser.php
@@ -3140,7 +3140,7 @@ class Parser {
 	 * @private
 	 */
 	function braceSubstitution( $piece, $frame ) {
-		global $wgContLang, $wgNonincludableNamespaces;
+		global $wgContLang, $wgNonincludableNamespaces, $wgEnableInterwikiTranscluding, $wgEnableInterwikiTemplatesTracking;
 		wfProfileIn( __METHOD__ );
 		wfProfileIn( __METHOD__.'-setup' );
 
@@ -3148,7 +3148,6 @@ class Parser {
 		$found = false;             # $text has been filled
 		$nowiki = false;            # wiki markup in $text should be escaped
 		$isHTML = false;            # $text is HTML, armour it against wikitext transformation
-		$forceRawInterwiki = false; # Force interwiki transclusion to be done in raw mode not rendered
 		$isChildObj = false;        # $text is a DOM node needing expansion in a child frame
 		$isLocalObj = false;        # $text is a DOM node needing expansion in the current frame
 
@@ -3313,6 +3312,9 @@ class Parser {
 			}
 			$title = Title::newFromText( $part1, $ns );
 			if ( $title ) {
+				if ( !$title->isExternal() && $piece['interwiki'] !== '' ) {
+					$title->setInterwiki( $piece['interwiki'] );
+				}
 				$titleText = $title->getPrefixedText();
 				# Check for language variants if the template is not found
 				if ( $wgContLang->hasVariants() && $title->getArticleID() == 0 ) {
@@ -3375,18 +3377,22 @@ class Parser {
 					$text = "[[:$titleText]]";
 					$found = true;
 				}
-			} elseif ( $title->isTrans() ) {
-				# Interwiki transclusion
-				if ( $this->ot['html'] && !$forceRawInterwiki ) {
-					$text = $this->interwikiTransclude( $title, 'render' );
-					$isHTML = true;
-				} else {
-					$text = $this->interwikiTransclude( $title, 'raw' );
+			} elseif ( $wgEnableInterwikiTranscluding && $title->isTrans() ) {
+
+				$text = Interwiki::interwikiTransclude( $title );
+				$this->registerDistantTemplate( $title );
+
+				if ( $wgEnableInterwikiTemplatesTracking ) {
+					$this->registerDistantTemplate( $title );
+				}
+
+				if ( $text !== false ) {
 					# Preprocess it like a template
 					$text = $this->preprocessToDom( $text, self::PTD_FOR_INCLUSION );
+					$found = true;
 					$isChildObj = true;
 				}
-				$found = true;
+
 			}
 
 			# Do infinite loop check
@@ -3536,10 +3542,19 @@ class Parser {
 	}
 
 	/**
-	 * Fetch the unparsed text of a template and register a reference to it.
-	 * @param Title $title
-	 * @return mixed string or false
+	 * Register a distant template as used
 	 */
+	function registerDistantTemplate( $title ) {
+		$stuff = Parser::distantTemplateCallback( $title, $this );
+		$text = $stuff['text'];
+		$finalTitle = isset( $stuff['finalTitle'] ) ? $stuff['finalTitle'] : $title;
+		if ( isset( $stuff['deps'] ) ) {
+			foreach ( $stuff['deps'] as $dep ) {
+				$this->mOutput->addDistantTemplate( $dep['title'], $dep['page_id'], $dep['rev_id'] );
+			}
+		}
+	}
+
 	function fetchTemplate( $title ) {
 		$rv = $this->fetchTemplateAndTitle( $title );
 		return $rv[0];
@@ -3668,57 +3683,22 @@ class Parser {
 		return array( $file, $title );
 	}
 
-	/**
-	 * Transclude an interwiki link.
-	 *
-	 * @param $title Title
-	 * @param $action
-	 *
-	 * @return string
-	 */
-	function interwikiTransclude( $title, $action ) {
-		global $wgEnableScaryTranscluding;
-
-		if ( !$wgEnableScaryTranscluding ) {
-			return wfMsgForContent('scarytranscludedisabled');
-		}
-
-		$url = $title->getFullUrl( "action=$action" );
+	static function distantTemplateCallback( $title, $parser=false ) {
+		$text = '';
+		$rev_id = null;
+		$deps[] = array(
+			'title' => $title,
+			'page_id' => $title->getArticleID(),
+			'rev_id' => $rev_id );
 
-		if ( strlen( $url ) > 255 ) {
-			return wfMsgForContent( 'scarytranscludetoolong' );
-		}
-		return $this->fetchScaryTemplateMaybeFromCache( $url );
-	}
-
-	/**
-	 * @param $url string
-	 * @return Mixed|String
-	 */
-	function fetchScaryTemplateMaybeFromCache( $url ) {
-		global $wgTranscludeCacheExpiry;
-		$dbr = wfGetDB( DB_SLAVE );
-		$tsCond = $dbr->timestamp( time() - $wgTranscludeCacheExpiry );
-		$obj = $dbr->selectRow( 'transcache', array('tc_time', 'tc_contents' ),
-				array( 'tc_url' => $url, "tc_time >= " . $dbr->addQuotes( $tsCond ) ) );
-		if ( $obj ) {
-			return $obj->tc_contents;
-		}
+		$finalTitle = $title;
 
-		$text = Http::get( $url );
-		if ( !$text ) {
-			return wfMsgForContent( 'scarytranscludefailed', $url );
+		return array(
+			'text' => $text,
+			'finalTitle' => $finalTitle,
+			'deps' => $deps );
 		}
 
-		$dbw = wfGetDB( DB_MASTER );
-		$dbw->replace( 'transcache', array('tc_url'), array(
-			'tc_url' => $url,
-			'tc_time' => $dbw->timestamp( time() ),
-			'tc_contents' => $text)
-		);
-		return $text;
-	}
-
 	/**
 	 * Triple brace replacement -- used for template arguments
 	 * @private
diff --git a/includes/parser/ParserOutput.php b/includes/parser/ParserOutput.php
index c643d75617..045a85250c 100644
--- a/includes/parser/ParserOutput.php
+++ b/includes/parser/ParserOutput.php
@@ -121,6 +121,8 @@ class ParserOutput extends CacheTime {
 		$mLinks = array(),            # 2-D map of NS/DBK to ID for the links in the document. ID=zero for broken.
 		$mTemplates = array(),        # 2-D map of NS/DBK to ID for the template references. ID=zero for broken.
 		$mTemplateIds = array(),      # 2-D map of NS/DBK to rev ID for the template references. ID=zero for broken.
+		$mDistantTemplates = array(),   # 3-D map of WIKIID/NS/DBK to ID for the template references. ID=zero for broken.
+		$mDistantTemplateIds = array(), # 3-D map of WIKIID/NS/DBK to rev ID for the template references. ID=zero for broken.
 		$mImages = array(),           # DB keys of the images used, in the array key only
 		$mImageTimeKeys = array(),	  # DB keys of the images used mapped to sha1 and MW timestamp
 		$mExternalLinks = array(),    # External link URLs, in the key only
@@ -191,6 +193,8 @@ class ParserOutput extends CacheTime {
 	function getEditSectionTokens()      { return $this->mEditSectionTokens; }
 	function &getLinks()                 { return $this->mLinks; }
 	function &getTemplates()             { return $this->mTemplates; }
+	function &getDistantTemplates()      { return $this->mDistantTemplates; }
+	function &getDistantTemplateIds()    { return $this->mDistantTemplateIds; }
 	function &getTemplateIds()           { return $this->mTemplateIds; }
 	function &getImages()                { return $this->mImages; }
 	function &getImageTimeKeys()         { return $this->mImageTimeKeys; }
@@ -312,6 +316,31 @@ class ParserOutput extends CacheTime {
 		$this->mTemplateIds[$ns][$dbk] = $rev_id; // For versioning
 	}
 
+	function addDistantTemplate( $title, $page_id, $rev_id ) {
+		$prefix = $title->getInterwiki();
+		if ( $prefix !=='' ) {
+			$ns = $title->getNamespace();
+			$dbk = $title->getDBkey();
+			
+			if ( !isset( $this->mDistantTemplates[$prefix] ) ) {
+				$this->mDistantTemplates[$prefix] = array();
+			}
+			if ( !isset( $this->mDistantTemplates[$prefix][$ns] ) ) {
+				$this->mDistantTemplates[$prefix][$ns] = array();
+			}
+			$this->mDistantTemplates[$prefix][$ns][$dbk] = $page_id;
+
+			// For versioning
+			if ( !isset( $this->mDistantTemplateIds[$prefix] ) ) {
+				$this->mDistantTemplateIds[$prefix] = array();
+			}
+			if ( !isset( $this->mDistantTemplateIds[$prefix][$ns] ) ) {
+				$this->mDistantTemplateIds[$prefix][$ns] = array();
+			}
+			$this->mDistantTemplateIds[$prefix][$ns][$dbk] = $rev_id;
+		}
+	}
+	
 	/**
 	 * @param $title Title object, must be an interwiki link
 	 * @throws MWException if given invalid input
diff --git a/includes/parser/Preprocessor_DOM.php b/includes/parser/Preprocessor_DOM.php
index 5b79876bea..dcda8a211f 100644
--- a/includes/parser/Preprocessor_DOM.php
+++ b/includes/parser/Preprocessor_DOM.php
@@ -1038,7 +1038,8 @@ class PPFrame_DOM implements PPFrame {
 						$params = array(
 							'title' => new PPNode_DOM( $title ),
 							'parts' => new PPNode_DOM( $parts ),
-							'lineStart' => $lineStart );
+							'lineStart' => $lineStart,
+							'interwiki' => $this->title->getInterwiki( ) );
 						$ret = $this->parser->braceSubstitution( $params, $this );
 						if ( isset( $ret['object'] ) ) {
 							$newIterator = $ret['object'];
diff --git a/includes/parser/Preprocessor_Hash.php b/includes/parser/Preprocessor_Hash.php
index c2d7d3d8de..50af6b6b63 100644
--- a/includes/parser/Preprocessor_Hash.php
+++ b/includes/parser/Preprocessor_Hash.php
@@ -976,6 +976,7 @@ class PPFrame_Hash implements PPFrame {
 					if ( $flags & PPFrame::NO_TEMPLATES ) {
 						$newIterator = $this->virtualBracketedImplode( '{{', '|', '}}', $bits['title'], $bits['parts'] );
 					} else {
+						$bits['interwiki'] = $this->title->getInterwiki( );
 						$ret = $this->parser->braceSubstitution( $bits, $this );
 						if ( isset( $ret['object'] ) ) {
 							$newIterator = $ret['object'];
diff --git a/includes/specials/SpecialGlobalFileUsage.php b/includes/specials/SpecialGlobalFileUsage.php
new file mode 100644
index 0000000000..e376ea6821
--- /dev/null
+++ b/includes/specials/SpecialGlobalFileUsage.php
@@ -0,0 +1,224 @@
+<?php
+/**
+ * Special page to show global file usage. Also contains hook functions for
+ * showing usage on an image page.
+ */
+
+class SpecialGlobalFileUsage extends SpecialPage {
+	public function __construct() {
+		parent::__construct( 'GlobalFileUsage' );
+	}
+
+	/**
+	 * Entry point
+	 */
+	public function execute( $par ) {
+		global $wgOut, $wgRequest;
+
+		$target = $par ? $par : $wgRequest->getVal( 'target' );
+		$this->target = Title::makeTitleSafe( NS_FILE, $target );
+
+		$this->filterLocal = $wgRequest->getCheck( 'filterlocal' );
+
+		$this->setHeaders();
+
+		$this->showForm();
+
+		if ( is_null( $this->target ) )	{
+			$wgOut->setPageTitle( wfMsg( 'globalfileusage' ) );
+			return;
+		}
+
+		$wgOut->setPageTitle( wfMsg( 'globalfileusage-for', $this->target->getPrefixedText() ) );
+
+		$this->showResult();
+	}
+	
+	/**
+	 * Shows the search form
+	 */
+	private function showForm() {
+		global $wgScript, $wgOut, $wgRequest;
+
+		/* Build form */
+		$html = Xml::openElement( 'form', array( 'action' => $wgScript ) ) . "\n";
+		// Name of SpecialPage
+		$html .= Xml::hidden( 'title', $this->getTitle()->getPrefixedText() ) . "\n";
+		// Limit
+		$html .= Xml::hidden( 'limit', $wgRequest->getInt( 'limit', 50 ) );
+		// Input box with target prefilled if available
+		$formContent = "\t" . Xml::input( 'target', 40, is_null( $this->target ) ? ''
+					: $this->target->getText() )
+		// Submit button
+			. "\n\t" . Xml::element( 'input', array(
+					'type' => 'submit',
+					'value' => wfMsg( 'globalfileusage-ok' )
+					) )
+		// Filter local checkbox
+			. "\n\t<p>" . Xml::checkLabel( wfMsg( 'globalfileusage-filterlocal' ),
+					'filterlocal', 'mw-filterlocal', $this->filterLocal ) . '</p>';
+		
+		if ( !is_null( $this->target ) && wfFindFile( $this->target ) ) {
+			// Show the image if it exists
+			global $wgUser, $wgContLang;
+			$skin = $wgUser->getSkin();
+
+			$html .= $skin->makeImageLinkObj( $this->target,
+					$this->target->getPrefixedText(),
+					/* $alt */ '', /* $align */ $wgContLang->alignEnd(),
+					/* $handlerParams */ array(), /* $framed */ false,
+					/* $thumb */ true );
+		}
+		
+		// Wrap the entire form in a nice fieldset
+		$html .= Xml::fieldSet( wfMsg( 'globalfileusage-text' ), $formContent ) . "\n</form>";
+
+		$wgOut->addHtml( $html );
+	}
+
+	/**
+	 * Creates as queryer and executes it based on $wgRequest
+	 */
+	private function showResult() {
+		global $wgRequest;
+
+		$query = new GlobalUsageQuery( $this->target );
+
+		// Extract params from $wgRequest
+		if ( $wgRequest->getText( 'from' ) ) {
+			$query->setOffset( $wgRequest->getText( 'from' ) );
+		} elseif ( $wgRequest->getText( 'to' ) ) {
+			$query->setOffset( $wgRequest->getText( 'to' ), true );
+		}
+		$query->setLimit( $wgRequest->getInt( 'limit', 50 ) );
+		$query->filterLocal( $this->filterLocal );
+
+		// Perform query
+		$query->searchFile();
+
+		// Show result
+		global $wgOut;
+
+		// Don't show form element if there is no data
+		if ( $query->count() == 0 ) {
+			$wgOut->addWikiMsg( 'globalfileusage-no-results', $this->target->getPrefixedText() );
+			return;
+		}
+
+		$offset = $query->getOffsetString();
+		$navbar = $this->getNavBar( $query );
+		$targetName = $this->target->getText();
+
+		// Top navbar
+		$wgOut->addHtml( $navbar );
+
+		$wgOut->addHtml( '<div id="mw-globalfileusage-result">' );
+		foreach ( $query->getSingleResult() as $wiki => $result ) {
+			$wgOut->addHtml(
+					'<h2>' . wfMsgExt(
+						'globalfileusage-on-wiki', 'parseinline',
+						$targetName, WikiMap::getWikiName( $wiki ) )
+					. "</h2><ul>\n" );
+			foreach ( $result as $item ) {
+				$wgOut->addHtml( "\t<li>" . self::formatItem( $item ) . "</li>\n" );
+			}
+			$wgOut->addHtml( "</ul>\n" );
+		}
+		$wgOut->addHtml( '</div>' );
+
+		// Bottom navbar
+		$wgOut->addHtml( $navbar );
+	}
+	/**
+	 * Helper to format a specific item
+	 */
+	public static function formatItem( $item ) {
+		if ( !$item['namespace'] ) {
+			$page = $item['title'];
+		} else {
+			$page = "{$item['namespace']}:{$item['title']}";
+		}
+
+		$link = WikiMap::makeForeignLink( $item['wiki'], $page,
+				str_replace( '_', ' ', $page ) );
+		// Return only the title if no link can be constructed
+		return $link === false ? $page : $link;
+	}
+
+	/**
+	 * Helper function to create the navbar, stolen from wfViewPrevNext
+	 * 
+	 * @param $query GlobalUsageQuery An executed GlobalUsageQuery object
+	 * @return string Navbar HTML
+	 */
+	protected function getNavBar( $query ) {
+		global $wgLang, $wgUser;
+
+		$skin = $wgUser->getSkin();
+
+		$target = $this->target->getText();
+		$limit = $query->getLimit();
+		$fmtLimit = $wgLang->formatNum( $limit );
+	
+		# Find out which strings are for the prev and which for the next links
+		$offset = $query->getOffsetString();
+		$continue = $query->getContinueFileString();
+		if ( $query->isReversed() ) {
+			$from = $offset;
+			$to = $continue;
+		} else {
+			$from = $continue;
+			$to = $offset;
+		}
+
+		# Get prev/next link display text
+		$prev =  wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
+		$next =  wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
+		# Get prev/next link title text
+		$pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
+		$nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
+
+		# Fetch the title object
+		$title = $this->getTitle();
+
+		# Make 'previous' link
+		if ( $to ) {
+			$attr = array( 'title' => $pTitle, 'class' => 'mw-prevlink' );
+			$q = array( 'limit' => $limit, 'to' => $to, 'target' => $target );
+			if ( $this->filterLocal )
+				$q['filterlocal'] = '1';
+			$plink = $skin->link( $title, $prev, $attr, $q );
+		} else {
+			$plink = $prev;
+		}
+
+		# Make 'next' link
+		if ( $from ) {
+			$attr = array( 'title' => $nTitle, 'class' => 'mw-nextlink' );
+			$q = array( 'limit' => $limit, 'from' => $from, 'target' => $target );
+			if ( $this->filterLocal )
+				$q['filterlocal'] = '1';
+			$nlink = $skin->link( $title, $next, $attr, $q );
+		} else {
+			$nlink = $next;
+		}
+
+		# Make links to set number of items per page
+		$numLinks = array();
+		foreach ( array( 20, 50, 100, 250, 500 ) as $num ) {
+			$fmtLimit = $wgLang->formatNum( $num );
+			
+			$q = array( 'offset' => $offset, 'limit' => $num, 'target' => $target );
+			if ( $this->filterLocal )
+				$q['filterlocal'] = '1';
+			$lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $num );
+			$attr = array( 'title' => $lTitle, 'class' => 'mw-numlink' );
+
+			$numLinks[] = $skin->link( $title, $fmtLimit, $attr, $q );
+		}
+		$nums = $wgLang->pipeList( $numLinks );
+
+		return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
+	}
+}
+
diff --git a/includes/specials/SpecialGlobalTemplateUsage.php b/includes/specials/SpecialGlobalTemplateUsage.php
new file mode 100644
index 0000000000..5f7e8aea1f
--- /dev/null
+++ b/includes/specials/SpecialGlobalTemplateUsage.php
@@ -0,0 +1,207 @@
+<?php
+/**
+ * This file has been copied from Extension:GlobalUsage and adapted
+ * to show the usage of a template instead of a file.
+ * Special page to show global template usage. Also contains hook functions for
+ * showing usage on an template page.
+ * 
+ * @author Bryan Tong Minh <bryan.tongminh@gmail.com>
+ * @author Peter Potrowl <peter017@gmail.com>
+ */
+
+class SpecialGlobalTemplateUsage extends SpecialPage {
+	public function __construct() {
+		parent::__construct( 'GlobalTemplateUsage' );
+	}
+
+	/**
+	 * Entry point
+	 */
+	public function execute( $par ) {
+		global $wgOut, $wgRequest;
+
+		$target = $par ? $par : $wgRequest->getVal( 'target' );
+		$this->target = Title::newFromText( $target );
+
+		$this->setHeaders();
+
+		$this->showForm();
+
+		if ( is_null( $this->target ) )	{
+			$wgOut->setPageTitle( wfMsg( 'globaltemplateusage' ) );
+			return;
+		}
+
+		$wgOut->setPageTitle( wfMsg( 'globaltemplateusage-for', $this->target->getPrefixedText() ) );
+
+		$this->showResult();
+	}
+	
+	/**
+	 * Shows the search form
+	 */
+	private function showForm() {
+		global $wgScript, $wgOut, $wgRequest;
+
+		/* Build form */
+		$html = Xml::openElement( 'form', array( 'action' => $wgScript ) ) . "\n";
+		// Name of SpecialPage
+		$html .= Xml::hidden( 'title', $this->getTitle( )->getPrefixedText( ) ) . "\n";
+		// Limit
+		$html .= Xml::hidden( 'limit', $wgRequest->getInt( 'limit', 50 ) );
+		// Input box with target prefilled if available
+		$formContent = "\t" . Xml::input( 'target', 40, is_null( $this->target ) ? ''
+					: $this->target->getPrefixedText( ) )
+		// Submit button
+			. "\n\t" . Xml::element( 'input', array(
+					'type' => 'submit',
+					'value' => wfMsg( 'globaltemplateusage-ok' )
+					) );
+		
+		// Wrap the entire form in a nice fieldset
+		$html .= Xml::fieldSet( wfMsg( 'globaltemplateusage-text' ), $formContent ) . "\n</form>";
+
+		$wgOut->addHtml( $html );
+	}
+
+	/**
+	 * Creates as queryer and executes it based on $wgRequest
+	 */
+	private function showResult() {
+		global $wgRequest;
+
+		$query = new GlobalUsageQuery( $this->target );
+
+		// Extract params from $wgRequest
+		if ( $wgRequest->getText( 'from' ) ) {
+			$query->setOffset( $wgRequest->getText( 'from' ) );
+		} elseif ( $wgRequest->getText( 'to' ) ) {
+			$query->setOffset( $wgRequest->getText( 'to' ), true );			
+		}
+		$query->setLimit( $wgRequest->getInt( 'limit', 50 ) );
+
+		// Perform query
+		$query->searchTemplate();
+
+		// Show result
+		global $wgOut;
+
+		// Don't show form element if there is no data
+		if ( $query->count() == 0 ) {
+			$wgOut->addWikiMsg( 'globaltemplateusage-no-results', $this->target->getPrefixedText( ) );
+			return;
+		}
+
+		$offset = $query->getOffsetString( );
+		$navbar = $this->getNavBar( $query );
+		$targetName = $this->target->getPrefixedText( );
+
+		// Top navbar
+		$wgOut->addHtml( $navbar );
+
+		$wgOut->addHtml( '<div id="mw-globaltemplateusage-result">' );
+		foreach ( $query->getSingleResult() as $wiki => $result ) {
+			$wgOut->addHtml(
+					'<h2>' . wfMsgExt(
+						'globaltemplateusage-on-wiki', 'parseinline',
+						$targetName, WikiMap::getWikiName( $wiki ) )
+					. "</h2><ul>\n" );
+			foreach ( $result as $item ) {
+				$wgOut->addHtml( "\t<li>" . self::formatItem( $item ) . "</li>\n" );
+			}
+			$wgOut->addHtml( "</ul>\n" );
+		}
+		$wgOut->addHtml( '</div>' );
+
+		// Bottom navbar
+		$wgOut->addHtml( $navbar );
+	}
+	
+	/**
+	 * Helper to format a specific item
+	 */
+	public static function formatItem( $item ) {
+		if ( !$item['namespace'] ) {
+			$page = $item['title'];
+		} else {
+			$page = "{$item['namespace']}:{$item['title']}";
+		}
+
+		$link = WikiMap::makeForeignLink( $item['wiki'], $page,
+				str_replace( '_', ' ', $page ) );
+		// Return only the title if no link can be constructed
+		return $link === false ? $page : $link;
+	}
+
+	/**
+	 * Helper function to create the navbar, stolen from wfViewPrevNext
+	 * 
+	 * @param $query GlobalTemplateUsageQuery An executed GlobalTemplateUsageQuery object
+	 * @return string Navbar HTML
+	 */
+	protected function getNavBar( $query ) {
+		global $wgLang, $wgUser;
+
+		$skin = $wgUser->getSkin();
+
+		$target = $this->target->getPrefixedText();
+		$limit = $query->getLimit();
+		$fmtLimit = $wgLang->formatNum( $limit );
+	
+		# Find out which strings are for the prev and which for the next links
+		$offset = $query->getOffsetString();
+		$continue = $query->getContinueTemplateString();
+		if ( $query->isReversed() ) {
+			$from = $offset;
+			$to = $continue;
+		} else {
+			$from = $continue;
+			$to = $offset;
+		}
+
+		# Get prev/next link display text
+		$prev =  wfMsgExt( 'prevn', array( 'parsemag', 'escape' ), $fmtLimit );
+		$next =  wfMsgExt( 'nextn', array( 'parsemag', 'escape' ), $fmtLimit );
+		# Get prev/next link title text
+		$pTitle = wfMsgExt( 'prevn-title', array( 'parsemag', 'escape' ), $fmtLimit );
+		$nTitle = wfMsgExt( 'nextn-title', array( 'parsemag', 'escape' ), $fmtLimit );
+
+		# Fetch the title object
+		$title = $this->getTitle();
+
+		# Make 'previous' link
+		if ( $to ) {
+			$attr = array( 'title' => $pTitle, 'class' => 'mw-prevlink' );
+			$q = array( 'limit' => $limit, 'to' => $to, 'target' => $target );
+			$plink = $skin->link( $title, $prev, $attr, $q );
+		} else {
+			$plink = $prev;
+		}
+
+		# Make 'next' link
+		if ( $from ) {
+			$attr = array( 'title' => $nTitle, 'class' => 'mw-nextlink' );
+			$q = array( 'limit' => $limit, 'from' => $from, 'target' => $target );
+			$nlink = $skin->link( $title, $next, $attr, $q );
+		} else {
+			$nlink = $next;
+		}
+
+		# Make links to set number of items per page
+		$numLinks = array();
+		foreach ( array( 20, 50, 100, 250, 500 ) as $num ) {
+			$fmtLimit = $wgLang->formatNum( $num );
+			
+			$q = array( 'offset' => $offset, 'limit' => $num, 'target' => $target );
+			$lTitle = wfMsgExt( 'shown-title', array( 'parsemag', 'escape' ), $num );
+			$attr = array( 'title' => $lTitle, 'class' => 'mw-numlink' );
+
+			$numLinks[] = $skin->link( $title, $fmtLimit, $attr, $q );
+		}
+		$nums = $wgLang->pipeList( $numLinks );
+
+		return wfMsgHtml( 'viewprevnext', $plink, $nlink, $nums );
+	}
+}
+
+
diff --git a/languages/messages/MessagesEn.php b/languages/messages/MessagesEn.php
index 22a153ca99..83bc114163 100644
--- a/languages/messages/MessagesEn.php
+++ b/languages/messages/MessagesEn.php
@@ -458,6 +458,8 @@ $specialPageAliases = array(
 	'Watchlist'                 => array( 'Watchlist' ),
 	'Whatlinkshere'             => array( 'WhatLinksHere' ),
 	'Withoutinterwiki'          => array( 'WithoutInterwiki' ),
+	'Globalfileusage'           => array( 'GlobalFileUsage' ),
+	'Globaltemplateusage'       => array( 'GlobalTemplateUsage' ),
 );
 
 /**
@@ -1402,6 +1404,9 @@ The latest log entry is provided below for reference:",
 'templatesused'                    => '{{PLURAL:$1|Template|Templates}} used on this page:',
 'templatesusedpreview'             => '{{PLURAL:$1|Template|Templates}} used in this preview:',
 'templatesusedsection'             => '{{PLURAL:$1|Template|Templates}} used in this section:',
+'distanttemplatesused'             => 'Distant {{PLURAL:$1|template|templates}} used on this page:',
+'distanttemplatesusedpreview'      => 'Distant {{PLURAL:$1|template|templates}} used in this preview:',
+'distanttemplatesusedsection'      => 'Distant {{PLURAL:$1|template|templates}} used in this section:',
 'template-protected'               => '(protected)',
 'template-semiprotected'           => '(semi-protected)',
 'hiddencategories'                 => 'This page is a member of {{PLURAL:$1|1 hidden category|$1 hidden categories}}:',
@@ -4582,6 +4587,30 @@ Enter the file name without the "{{ns:file}}:" prefix.',
 'compare-title-not-exists'    => 'The title you specified does not exist.',
 'compare-revision-not-exists' => 'The revision you specified does not exist.',
 
+# Special:GlobalFileUsage
+'globalfileusage'      => 'Global file usage',
+'globalfileusage-for'  => 'Global file usage for "$1"',
+'globalfileusage-desc' => '[[Special:GlobalFileUsage|Special page]] to view global file usage',
+'globalfileusage-ok'   => 'Search',
+'globalfileusage-text' => 'Search global file usage',
+'globalfileusage-no-results' => '[[$1]] is not used on other wikis.',
+'globalfileusage-on-wiki' => 'Usage on $2',
+'globalfileusage-of-file' => 'The following other wikis use this file:',
+'globalfileusage-more' => 'View [[{{#Special:GlobalUsage}}/$1|more global usage]] of this file.',
+'globalfileusage-filterlocal' => 'Do not show local usage',
+
+# Special:GlobalTemplateUsage
+'globaltemplateusage'      => 'Global template usage',
+'globaltemplateusage-for'  => 'Global template usage for "$1"',
+'globaltemplateusage-desc' => '[[Special:GlobalTemplateUsage|Special page]] to view global template usage',
+'globaltemplateusage-ok'   => 'Search',
+'globaltemplateusage-text' => 'Search global template usage',
+'globaltemplateusage-no-results' => '[[$1]] is not used on other wikis.',
+'globaltemplateusage-on-wiki' => 'Usage on $2',
+'globaltemplateusage-of-file' => 'The following other wikis use this template:',
+'globaltemplateusage-more' => 'View [[{{#Special:GlobalUsage}}/$1|more global usage]] of this template.',
+'globaltemplateusage-filterlocal' => 'Do not show local usage',
+
 # Database error messages
 'dberr-header'      => 'This wiki has a problem',
 'dberr-problems'    => 'Sorry!
diff --git a/languages/messages/MessagesQqq.php b/languages/messages/MessagesQqq.php
index f021f8e09d..a1d5fdef0c 100644
--- a/languages/messages/MessagesQqq.php
+++ b/languages/messages/MessagesQqq.php
@@ -4259,6 +4259,16 @@ Used on [[Special:Tags]]. Verb. Used as display text on a link to create/edit a
 
 {{Identical|Other}}',
 
+# Special:GlobalFileUsage
+'globalfileusage-for'  => '$1 is a file name',
+'globalfileusage-no-results' => '$1 is a file name',
+'globalfileusage-on-wiki' => '$2 is a wiki name',
+
+# Special:GlobalTemplateUsage
+'globaltemplateusage-for'  => '$1 is a template name',
+'globaltemplateusage-no-results' => '$1 is a template name',
+'globaltemplateusage-on-wiki' => '$2 is a wiki name',
+
 # SQLite database support
 'sqlite-has-fts' => 'Shown on Special:Version, $1 is version',
 'sqlite-no-fts'  => 'Shown on Special:Version, $1 is version',
diff --git a/maintenance/archives/patch-globalinterwiki.sql b/maintenance/archives/patch-globalinterwiki.sql
new file mode 100644
index 0000000000..6571a5aff2
--- /dev/null
+++ b/maintenance/archives/patch-globalinterwiki.sql
@@ -0,0 +1,10 @@
+-- Table associating distant wiki IDs with their interwiki prefixes.
+CREATE TABLE /*_*/globalinterwiki (
+  -- The wiki ID of the wiki
+  giw_wikiid varchar(64) NOT NULL,
+
+  -- The interwiki prefix of that wiki
+  giw_prefix varchar(32) NOT NULL
+
+) /*$wgDBTableOptions*/;
+CREATE UNIQUE INDEX /*i*/giw_index ON /*_*/globalinterwiki (giw_wikiid, giw_prefix);
diff --git a/maintenance/archives/patch-globalnamespaces.sql b/maintenance/archives/patch-globalnamespaces.sql
new file mode 100644
index 0000000000..91b3578f6a
--- /dev/null
+++ b/maintenance/archives/patch-globalnamespaces.sql
@@ -0,0 +1,14 @@
+-- Table listing distant wiki namespace texts.
+CREATE TABLE /*_*/globalnamespaces (
+  -- The wiki ID of the remote wiki
+  gn_wiki varchar(64) NOT NULL,
+
+  -- The namespace ID of the transcluded page on that wiki
+  gn_namespace int NOT NULL,
+
+  -- The namespace text of transcluded page
+  -- Needed for display purposes, since the local namespace ID doesn't necessarily match a distant one
+  gn_namespacetext varchar(255) NOT NULL
+
+) /*$wgDBTableOptions*/;
+CREATE UNIQUE INDEX /*i*/gn_index ON /*_*/globalnamespaces (gn_wiki, gn_namespace, gn_namespacetext);
diff --git a/maintenance/archives/patch-globaltemplatelinks.sql b/maintenance/archives/patch-globaltemplatelinks.sql
new file mode 100644
index 0000000000..d2da21bd82
--- /dev/null
+++ b/maintenance/archives/patch-globaltemplatelinks.sql
@@ -0,0 +1,36 @@
+-- Table tracking interwiki transclusions in the spirit of templatelinks.
+-- This table tracks transclusions of this wiki's templates on another wiki
+-- The gtl_from_* fields describe the (remote) page the template is transcluded from
+-- The gtl_to_* fields describe the (local) template being transcluded
+CREATE TABLE /*_*/globaltemplatelinks (
+  -- The wiki ID of the remote wiki
+  gtl_from_wiki varchar(64) NOT NULL,
+
+  -- The page ID of the calling page on the remote wiki
+  gtl_from_page int unsigned NOT NULL,
+
+  -- The namespace of the calling page on the remote wiki
+  -- Needed for display purposes, since the foreign namespace ID doesn't necessarily match a local one
+  -- The link between the namespace and the namespace name is made by the globalnamespaces table 
+  gtl_from_namespace int NOT NULL,
+
+  -- The title of the calling page on the remote wiki
+  -- Needed for display purposes
+  gtl_from_title varchar(255) binary NOT NULL,
+
+  -- The interwiki prefix of the wiki that hosts the transcluded page
+  gtl_to_prefix varchar(32) NOT NULL,
+
+  -- The namespace of the transcluded page on that wiki
+  gtl_to_namespace int NOT NULL,
+
+  -- The namespace name of transcluded page
+  -- Needed for display purposes, since the local namespace ID doesn't necessarily match a distant one
+  gtl_to_namespacetext varchar(255) NOT NULL,
+
+  -- The title of the transcluded page on that wiki
+  gtl_to_title varchar(255) binary NOT NULL
+) /*$wgDBTableOptions*/;
+
+CREATE UNIQUE INDEX /*i*/gtl_to_from ON /*_*/globaltemplatelinks (gtl_to_prefix, gtl_to_namespace, gtl_to_title, gtl_from_wiki, gtl_from_page);
+CREATE UNIQUE INDEX /*i*/gtl_from_to ON /*_*/globaltemplatelinks (gtl_from_wiki, gtl_from_page, gtl_to_prefix, gtl_to_namespace, gtl_to_title);
diff --git a/maintenance/language/messages.inc b/maintenance/language/messages.inc
index 2d89268798..ed0ad65062 100644
--- a/maintenance/language/messages.inc
+++ b/maintenance/language/messages.inc
@@ -640,6 +640,9 @@ $wgMessageStructure = array(
 		'templatesused',
 		'templatesusedpreview',
 		'templatesusedsection',
+		'distanttemplatesused',
+		'distanttemplatesusedpreview',
+		'distanttemplatesusedsection',
 		'template-protected',
 		'template-semiprotected',
 		'hiddencategories',
diff --git a/maintenance/tables.sql b/maintenance/tables.sql
index 2ab431f49a..556fd54d8c 100644
--- a/maintenance/tables.sql
+++ b/maintenance/tables.sql
@@ -1480,4 +1480,68 @@ CREATE TABLE /*_*/config (
 -- Should cover *most* configuration - strings, ints, bools, etc.
 CREATE INDEX /*i*/cf_name_value ON /*_*/config (cf_name,cf_value(255));
 
+-- Table tracking interwiki transclusions in the spirit of templatelinks.
+-- This table tracks transclusions of this wiki's templates on another wiki
+-- The gtl_from_* fields describe the (remote) page the template is transcluded from
+-- The gtl_to_* fields describe the (local) template being transcluded
+CREATE TABLE /*_*/globaltemplatelinks (
+  -- The wiki ID of the remote wiki
+  gtl_from_wiki varchar(64) NOT NULL,
+
+  -- The page ID of the calling page on the remote wiki
+  gtl_from_page int unsigned NOT NULL,
+
+  -- The namespace of the calling page on the remote wiki
+  -- Needed for display purposes, since the foreign namespace ID doesn't necessarily match a local one
+  -- The link between the namespace and the namespace name is made by the globalnamespaces table 
+  gtl_from_namespace int NOT NULL,
+
+  -- The title of the calling page on the remote wiki
+  -- Needed for display purposes
+  gtl_from_title varchar(255) binary NOT NULL,
+
+  -- The interwiki prefix of the wiki that hosts the transcluded page
+  gtl_to_prefix varchar(32) NOT NULL,
+
+  -- The namespace of the transcluded page on that wiki
+  gtl_to_namespace int NOT NULL,
+
+  -- The namespace name of transcluded page
+  -- Needed for display purposes, since the local namespace ID doesn't necessarily match a distant one
+  gtl_to_namespacetext varchar(255) NOT NULL,
+
+  -- The title of the transcluded page on that wiki
+  gtl_to_title varchar(255) binary NOT NULL
+) /*$wgDBTableOptions*/;
+
+CREATE UNIQUE INDEX /*i*/gtl_to_from ON /*_*/globaltemplatelinks (gtl_to_prefix, gtl_to_namespace, gtl_to_title, gtl_from_wiki, gtl_from_page);
+CREATE UNIQUE INDEX /*i*/gtl_from_to ON /*_*/globaltemplatelinks (gtl_from_wiki, gtl_from_page, gtl_to_prefix, gtl_to_namespace, gtl_to_title);
+
+-- Table listing distant wiki namespace texts.
+CREATE TABLE /*_*/globalnamespaces (
+  -- The wiki ID of the remote wiki
+  gn_wiki varchar(64) NOT NULL,
+
+  -- The namespace ID of the transcluded page on that wiki
+  gn_namespace int NOT NULL,
+
+  -- The namespace text of transcluded page
+  -- Needed for display purposes, since the local namespace ID doesn't necessarily match a distant one
+  gn_namespacetext varchar(255) NOT NULL
+
+) /*$wgDBTableOptions*/;
+CREATE UNIQUE INDEX /*i*/gn_index ON /*_*/globalnamespaces (gn_wiki, gn_namespace, gn_namespacetext);
+
+-- Table associating distant wiki IDs with their interwiki prefixes.
+CREATE TABLE /*_*/globalinterwiki (
+  -- The wiki ID of the wiki
+  giw_wikiid varchar(64) NOT NULL,
+
+  -- The interwiki prefix of that wiki
+  giw_prefix varchar(32) NOT NULL
+
+) /*$wgDBTableOptions*/;
+CREATE UNIQUE INDEX /*i*/giw_index ON /*_*/globalinterwiki (giw_wikiid, giw_prefix);
+
+
 -- vim: sw=2 sts=2 et
-- 
2.20.1