Fatal error: Uncaught Error: Undefined class constant 'MYSQL_ATTR_USE_BUFFERED_QUERY' in /var/www/html/includes/database/mysql/database.inc:56 Stack trace: #0 /var/www/html/includes/database/database.inc(1745): DatabaseConnection_mysql->__construct(Array) #1 /var/www/html/includes/database/database.inc(1535): Database::openConnection('default', 'default') #2 /var/www/html/includes/database/database.inc(2626): Database::getConnection() #3 /var/www/html/includes/cache.inc(359): db_escape_table('cache_bootstrap') #4 /var/www/html/includes/cache.inc(340): DrupalDatabaseCache->getMultiple(Array) #5 /var/www/html/includes/cache.inc(57): DrupalDatabaseCache->get('module_implemen...') #6 /var/www/html/includes/module.inc(762): cache_get('module_implemen...', 'cache_bootstrap') #7 /var/www/html/includes/module.inc(962): module_implements('system_theme_in...') #8 /var/www/html/modules/system/system.module(2514): module_invoke_all('system_theme_in...') #9 /var/www/html/includes/theme.inc(798): _system_rebuild_theme_data() #10 /var/w in /var/www/html/includes/database/mysql/database.inc on line 56