If you have a yml file you can create a php script and run the following to create the db from your yml.
$options = array(
'packagesPrefix' => 'Plugin',
'baseClassName' => 'MyDoctrineRecord',
'suffix' => '.php'
);
Doctrine_Core::generateModelsFromYaml('/path/to/yaml', '/path/to/model', $options);
In general Doctrine_Core has a few methods to create, drop and insert to db after you have set up the connection. It is pretty straight forward.