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(Cannot access the database)
Backtrace:
#0 /var/www/html/includes/libs/rdbms/database/DatabaseMySQL.php(134): Wikimedia\Rdbms\Database->newExceptionAfterConnectError()
#1 /var/www/html/includes/libs/rdbms/database/Database.php(268): Wikimedia\Rdbms\DatabaseMySQL->open()
#2 /var/www/html/includes/libs/rdbms/database/DatabaseFactory.php(156): Wikimedia\Rdbms\Database->initConnection()
#3 /var/www/html/extensions/Cargo/includes/CargoUtils.php(82): Wikimedia\Rdbms\DatabaseFactory->create()
#4 /var/www/html/extensions/Cargo/includes/parserfunctions/CargoStore.php(131): CargoUtils::getDB()
#5 /var/www/html/extensions/Cargo/includes/parserfunctions/CargoStore.php(108): CargoStore::storeTable()
#6 /var/www/html/includes/parser/Parser.php(3371): CargoStore::run()
#7 /var/www/html/includes/parser/Parser.php(3056): Parser->callParserFunction()
#8 /var/www/html/includes/parser/PPFrame_Hash.php(274): Parser->braceSubstitution()
#9 /var/www/html/includes/parser/Parser.php(3247): PPFrame_Hash->expand()
#10 /var/www/html/includes/parser/PPFrame_Hash.php(274): Parser->braceSubstitution()
#11 /var/www/html/includes/parser/Parser.php(2888): PPFrame_Hash->expand()
#12 /var/www/html/includes/parser/Parser.php(1544): Parser->replaceVariables()
#13 /var/www/html/includes/parser/Parser.php(651): Parser->internalParse()
#14 /var/www/html/includes/content/WikitextContentHandler.php(420): Parser->parse()
#15 /var/www/html/includes/content/ContentHandler.php(1760): WikitextContentHandler->fillParserOutput()
#16 /var/www/html/includes/content/Renderer/ContentRenderer.php(47): ContentHandler->getParserOutput()
#17 /var/www/html/includes/Revision/RenderedRevision.php(260): MediaWiki\Content\Renderer\ContentRenderer->getParserOutput()
#18 /var/www/html/includes/Revision/RenderedRevision.php(232): MediaWiki\Revision\RenderedRevision->getSlotParserOutputUncached()
#19 /var/www/html/includes/Revision/RevisionRenderer.php(223): MediaWiki\Revision\RenderedRevision->getSlotParserOutput()
#20 /var/www/html/includes/Revision/RevisionRenderer.php(164): MediaWiki\Revision\RevisionRenderer->combineSlotOutput()
#21 [internal function]: MediaWiki\Revision\RevisionRenderer->MediaWiki\Revision\{closure}()
#22 /var/www/html/includes/Revision/RenderedRevision.php(199): call_user_func()
#23 /var/www/html/includes/poolcounter/PoolWorkArticleView.php(84): MediaWiki\Revision\RenderedRevision->getRevisionParserOutput()
#24 /var/www/html/includes/poolcounter/PoolWorkArticleViewCurrent.php(104): PoolWorkArticleView->renderRevision()
#25 /var/www/html/includes/poolcounter/PoolCounterWork.php(167): PoolWorkArticleViewCurrent->doWork()
#26 /var/www/html/includes/page/ParserOutputAccess.php(304): PoolCounterWork->execute()
#27 /var/www/html/includes/page/Article.php(747): MediaWiki\Page\ParserOutputAccess->getParserOutput()
#28 /var/www/html/includes/page/Article.php(550): Article->generateContentOutput()
#29 /var/www/html/includes/actions/ViewAction.php(78): Article->view()
#30 /var/www/html/includes/MediaWiki.php(583): ViewAction->show()
#31 /var/www/html/includes/MediaWiki.php(363): MediaWiki->performAction()
#32 /var/www/html/includes/MediaWiki.php(960): MediaWiki->performRequest()
#33 /var/www/html/includes/MediaWiki.php(613): MediaWiki->main()
#34 /var/www/html/index.php(50): MediaWiki->run()
#35 /var/www/html/index.php(46): wfIndexMain()
#36 {main}