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(Cannot access the database)
Backtrace:
#0 /var/lib/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(904): Database->reportConnectionError('Too many connec...')
#1 /var/lib/mediawiki/includes/libs/rdbms/loadbalancer/LoadBalancer.php(579): LoadBalancer->reportConnectionError()
#2 /var/lib/mediawiki/includes/GlobalFunctions.php(3075): LoadBalancer->getConnection(0, Array, false)
#3 /var/lib/mediawiki/includes/Revision.php(322): wfGetDB(-1)
#4 /var/lib/mediawiki/includes/Revision.php(111): Revision::newFromConds(Array, 0)
#5 /var/lib/mediawiki/includes/MediaWiki.php(105): Revision::newFromId(22242)
#6 /var/lib/mediawiki/includes/MediaWiki.php(136): MediaWiki->parseTitle()
#7 /var/lib/mediawiki/includes/MediaWiki.php(766): MediaWiki->getTitle()
#8 /var/lib/mediawiki/includes/MediaWiki.php(512): MediaWiki->main()
#9 /var/lib/mediawiki/index.php(43): MediaWiki->run()
#10 {main}