/**
  * @return bool
  */
 public function perform()
 {
     // catalog_product_entity_tier_price should be migrated first to save same value_id as into magento1
     $sourceDocuments = array_keys($this->helper->getSourceDocumentFields());
     $this->progress->start(count($sourceDocuments), LogManager::LOG_LEVEL_INFO);
     $destinationName = $this->helper->getDestinationName();
     $this->destination->clearDocument($destinationName);
     $destDocument = $this->destination->getDocument($destinationName);
     foreach ($sourceDocuments as $sourceDocName) {
         $pageNumber = 0;
         $this->logger->debug('migrating', ['table' => $sourceDocName]);
         $this->progress->start($this->source->getRecordsCount($sourceDocName), LogManager::LOG_LEVEL_DEBUG);
         while (!empty($items = $this->source->getRecords($sourceDocName, $pageNumber))) {
             $pageNumber++;
             $destinationRecords = $destDocument->getRecords();
             foreach ($items as $recordData) {
                 unset($recordData['value_id']);
                 $this->progress->advance(LogManager::LOG_LEVEL_INFO);
                 $this->progress->advance(LogManager::LOG_LEVEL_DEBUG);
                 /** @var Record $destRecord */
                 $destRecord = $this->recordFactory->create(['document' => $destDocument, 'data' => $recordData]);
                 $destinationRecords->addRecord($destRecord);
             }
             $this->destination->saveRecords($destinationName, $destinationRecords);
         }
         $this->progress->finish(LogManager::LOG_LEVEL_DEBUG);
     }
     $this->progress->finish(LogManager::LOG_LEVEL_INFO);
     return true;
 }
 /**
  * {@inheritdoc}
  */
 public function perform()
 {
     $this->progress->start(count($this->helper->getSourceDocumentFields()));
     $sourceTotal = 0;
     $destinationTotal = $this->destination->getRecordsCount($this->helper->getDestinationName());
     foreach (array_keys($this->helper->getSourceDocumentFields()) as $sourceName) {
         $sourceTotal += $this->source->getRecordsCount($sourceName);
         $this->progress->advance();
     }
     if ($sourceTotal != $destinationTotal) {
         $this->errors[] = 'Mismatch of amount of entities in documents';
     }
     $this->progress->finish();
     return $this->checkForErrors(Logger::ERROR);
 }
 /**
  * Get iterations count for step
  *
  * @return int
  */
 protected function getIterationsCount()
 {
     return count($this->helper->getSourceDocumentFields()) + count($this->helper->getDestinationDocumentFields());
 }