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(Cannot access the database)
Backtrace:
#0 /var/www/mediawiki-1.39.7/includes/libs/rdbms/loadbalancer/LoadBalancer.php(972): Wikimedia\Rdbms\LoadBalancer->reportConnectionError()
#1 /var/www/mediawiki-1.39.7/includes/libs/rdbms/loadbalancer/LoadBalancer.php(944): Wikimedia\Rdbms\LoadBalancer->getServerConnection()
#2 /var/www/mediawiki-1.39.7/includes/libs/rdbms/database/DBConnRef.php(95): Wikimedia\Rdbms\LoadBalancer->getConnectionInternal()
#3 /var/www/mediawiki-1.39.7/includes/libs/rdbms/database/DBConnRef.php(101): Wikimedia\Rdbms\DBConnRef->ensureConnection()
#4 /var/www/mediawiki-1.39.7/includes/libs/rdbms/database/DBConnRef.php(344): Wikimedia\Rdbms\DBConnRef->__call()
#5 /var/www/mediawiki-1.39.7/includes/page/WikiPage.php(408): Wikimedia\Rdbms\DBConnRef->selectRow()
#6 /var/www/mediawiki-1.39.7/includes/page/WikiPage.php(430): WikiPage->pageData()
#7 /var/www/mediawiki-1.39.7/includes/page/WikiPage.php(470): WikiPage->pageDataFromTitle()
#8 /var/www/mediawiki-1.39.7/includes/page/WikiPage.php(587): WikiPage->loadPageData()
#9 /var/www/mediawiki-1.39.7/includes/page/WikiPage.php(661): WikiPage->exists()
#10 /var/www/mediawiki-1.39.7/includes/page/WikiPage.php(296): WikiPage->getContentModel()
#11 /var/www/mediawiki-1.39.7/includes/MediaWiki.php(437): WikiPage->getContentHandler()
#12 /var/www/mediawiki-1.39.7/includes/MediaWiki.php(320): MediaWiki->initializeArticle()
#13 /var/www/mediawiki-1.39.7/includes/MediaWiki.php(904): MediaWiki->performRequest()
#14 /var/www/mediawiki-1.39.7/includes/MediaWiki.php(562): MediaWiki->main()
#15 /var/www/mediawiki-1.39.7/index.php(50): MediaWiki->run()
#16 /var/www/mediawiki-1.39.7/index.php(46): wfIndexMain()
#17 {main}