code: public function findBy(array $criteria = [])
      {
          $queryBuilder = $this->connection->createQueryBuilder();
          $queryBuilder->from($this->table, 'identity');
          $queryBuilder->select([
              'identity.objectIdentifier',
              'identity.objectType',
              'identity.adapterIdentifier',
              'identity.adapterName',
          ]);
  
          foreach ($criteria as $key => $value) {
              $queryBuilder->andWhere($queryBuilder->expr()->eq($key, ':' . $key));
              $queryBuilder->setParameter(':' . $key, $value);
          }
  
          $result = $queryBuilder->execute()->fetchAll();
  
          return array_map(function (array $result) {
              return Identity::fromArray([
                  'objectIdentifier' => $result['objectIdentifier'],
                  'objectType' => $result['objectType'],
                  'adapterIdentifier' => $result['adapterIdentifier'],
                  'adapterName' => $result['adapterName'],
              ]);
          }, $result);
      }
docs: {@inheritdoc}