Warning: mysql_connect() [function.mysql-connect]: Unknown MySQL server host 'db' (110) in /var/www/html/redefine/php/data/RDFDatabaseQuery.php on line 295

Fatal error: Uncaught exception 'Exception' with message 'could not connect' in /var/www/html/redefine/php/data/RDFDatabaseQuery.php:296 Stack trace: #0 /var/www/html/redefine/php/data/RDFDatabaseQuery.php(312): RDFMYSQLQUERY->connect() #1 /var/www/html/redefine/php/data/RDFDatabaseQuery.php(176): RDFMYSQLQUERY->escape('`system__settin...') #2 /var/www/html/redefine/php/data/RDFDatabaseQuery.php(222): RDFDatabaseQuery->setValue('settingsTable', '`system__settin...') #3 /var/www/html/redefine/php/data/Session.php(101): RDFDatabaseQuery->setTable('settingsTable', 'settings') #4 /var/www/html/redefine/php/data/Session.php(72): SessionManager->initSystemSettings() #5 /var/www/html/redefine/php/data/Session.php(45): SessionManager->__construct() #6 /var/www/html/redefine/php/Main.php(53): SessionManager::getInstance() #7 /var/www/html/redefine/php/Main.php(36): Main->initSession() #8 /var/www/html/index.php(4): Main->__construct() #9 {main} thrown in /var/www/html/redefine/php/data/RDFDatabaseQuery.php on line 296