$this
            ->addOption('mysql-engine', null, InputOption::VALUE_REQUIRED,  'MySQL engine (MyISAM, InnoDB, ...)')
            ->addOption('schema-dir',   null, InputOption::VALUE_REQUIRED,  'The directory where the schema files are placed')
            ->addOption('output-dir',   null, InputOption::VALUE_REQUIRED,  'The output directory')
            ->addOption('validate',     null, InputOption::VALUE_NONE,      '')