Symfony doctrine set database name in migration

Question

I want execute migration only for specific database (exist more than 1 database).

public function up()
{
    $this->addColumn('user', 'tests', 'string', array('length' => '255'));
}

I try set:

public function up()
{
    $this->addColumn('database.user', 'tests', 'string', array('length' => '255'));
}

but it not work, symfony try execute this migration for all databases :)

How I can set database name ?