public function getDocumentDatabase($className)
{
$className = ltrim($className, '\\');
if (isset($this->documentDatabases[$className])) {
return $this->documentDatabases[$className];
}
$metadata = $this->metadataFactory->getMetadataFor($className);
$db = $metadata->getDatabase();
$db = $db ?: $this->config->getDefaultDB();
$db = $db ?: 'doctrine';
$this->documentDatabases[$className] = $this->connection->selectDatabase($db);
return $this->documentDatabases[$className];
}