Exception encountered, of type "mysqli_sql_exception"
[7bc40e612d1c3da592fbf661] /class-wiki/index.php/DFT_example_using_MATLAB_-_HW11 mysqli_sql_exception from line 105 of /var/www/class-wiki/includes/db/DatabaseMysqli.php: Connection refused
Backtrace:
#0 /var/www/class-wiki/includes/db/DatabaseMysqli.php(105): mysqli->real_connect()
#1 /var/www/class-wiki/includes/db/DatabaseMysqlBase.php(96): DatabaseMysqli->mysqlConnect()
#2 /var/www/class-wiki/includes/db/Database.php(544): DatabaseMysqlBase->open()
#3 /var/www/class-wiki/includes/db/DatabaseMysqlBase.php(56): DatabaseBase->__construct()
#4 /var/www/class-wiki/includes/db/Database.php(639): DatabaseMysqlBase->__construct()
#5 /var/www/class-wiki/includes/db/loadbalancer/LoadBalancer.php(828): DatabaseBase::factory()
#6 /var/www/class-wiki/includes/db/loadbalancer/LoadBalancer.php(681): LoadBalancer->reallyOpenConnection()
#7 /var/www/class-wiki/includes/db/loadbalancer/LoadBalancer.php(561): LoadBalancer->openConnection()
#8 /var/www/class-wiki/includes/GlobalFunctions.php(3155): LoadBalancer->getConnection()
#9 /var/www/class-wiki/includes/objectcache/SqlBagOStuff.php(165): wfGetDB()
#10 /var/www/class-wiki/includes/objectcache/SqlBagOStuff.php(247): SqlBagOStuff->getDB()
#11 /var/www/class-wiki/includes/objectcache/SqlBagOStuff.php(225): SqlBagOStuff->getMulti()
#12 /var/www/class-wiki/includes/objectcache/SqlBagOStuff.php(221): SqlBagOStuff->getWithToken()
#13 /var/www/class-wiki/includes/libs/objectcache/CachedBagOStuff.php(52): SqlBagOStuff->doGet()
#14 /var/www/class-wiki/includes/libs/objectcache/BagOStuff.php(179): CachedBagOStuff->doGet()
#15 /var/www/class-wiki/includes/session/SessionManager.php(929): BagOStuff->get()
#16 /var/www/class-wiki/includes/session/SessionInfo.php(149): MediaWiki\Session\SessionManager->generateSessionId()
#17 /var/www/class-wiki/includes/session/SessionProvider.php(171): MediaWiki\Session\SessionInfo->__construct()
#18 /var/www/class-wiki/includes/session/SessionManager.php(261): MediaWiki\Session\SessionProvider->newSessionInfo()
#19 /var/www/class-wiki/includes/session/SessionManager.php(235): MediaWiki\Session\SessionManager->getEmptySessionInternal()
#20 /var/www/class-wiki/includes/session/SessionManager.php(185): MediaWiki\Session\SessionManager->getEmptySession()
#21 /var/www/class-wiki/includes/WebRequest.php(700): MediaWiki\Session\SessionManager->getSessionForRequest()
#22 /var/www/class-wiki/includes/session/SessionManager.php(121): WebRequest->getSession()
#23 /var/www/class-wiki/includes/Setup.php(745): MediaWiki\Session\SessionManager::getGlobalSession()
#24 /var/www/class-wiki/includes/WebStart.php(137): require_once(string)
#25 /var/www/class-wiki/index.php(40): require(string)
#26 {main}