Im having the same issue and I am running with full paths, I am running a local dev env under MAMP pro on Mac.
[2017-09-13 12:44:30] mautic.NOTICE: DoctrineDBALExceptionConnectionException: An exception occured in driver: SQLSTATE[HY000]  No such file or directory (uncaught exception) at /Applications/MAMP/htdocs/mautic/vendor/doctrine/dbal/lib/Doctrine/DBAL/Driver/AbstractMySQLDriver.php line 103 while running console command
mautic:campaigns:trigger  
command Im running from the command line: php /Applications/MAMP/htdocs/mautic/app/console mautic:campaigns:trigger
php: version PHP 7.0.22