private function isOdmRelation(array $association)
    {
        return array_key_exists('type', $association) &&
               array_key_exists('reference', $association) &&
               array_key_exists('fieldName', $association) &&
               is_string($association['type']) &&
               is_bool($association['reference']) &&
               is_string($association['fieldName'])
        ;
    }
private function isOdmRelation(array $association)
    {
        return array_key_exists('type', $association) &&
               array_key_exists('reference', $association) &&
               array_key_exists('fieldName', $association) &&
               is_string($association['type']) &&
               is_bool($association['reference']) &&
               is_string($association['fieldName'])
        ;
    }
@param array $association

@return bool