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protected function SqlBase::initializeIterator in Drupal 8

Same name and namespace in other branches
  1. 9 core/modules/migrate/src/Plugin/migrate/source/SqlBase.php \Drupal\migrate\Plugin\migrate\source\SqlBase::initializeIterator()
  2. 10 core/modules/migrate/src/Plugin/migrate/source/SqlBase.php \Drupal\migrate\Plugin\migrate\source\SqlBase::initializeIterator()

Initializes the iterator with the source data.

Return value

\Iterator Returns an iteratable object of data for this source.

Overrides SourcePluginBase::initializeIterator

10 calls to SqlBase::initializeIterator()
Block::initializeIterator in core/modules/block/src/Plugin/migrate/source/Block.php
Initializes the iterator with the source data.
CommentType::initializeIterator in core/modules/comment/src/Plugin/migrate/source/d7/CommentType.php
Initializes the iterator with the source data.
File::initializeIterator in core/modules/file/src/Plugin/migrate/source/d6/File.php
Initializes the iterator with the source data.
File::initializeIterator in core/modules/file/src/Plugin/migrate/source/d7/File.php
Initializes the iterator with the source data.
Node::initializeIterator in core/modules/node/src/Plugin/migrate/source/d6/Node.php
Initializes the iterator with the source data.

... See full list

20 methods override SqlBase::initializeIterator()
Block::initializeIterator in core/modules/block/src/Plugin/migrate/source/Block.php
Initializes the iterator with the source data.
CommentType::initializeIterator in core/modules/comment/src/Plugin/migrate/source/d7/CommentType.php
Initializes the iterator with the source data.
CommentVariable::initializeIterator in core/modules/comment/src/Plugin/migrate/source/d6/CommentVariable.php
Initializes the iterator with the source data.
EntityTranslationSettings::initializeIterator in core/modules/content_translation/src/Plugin/migrate/source/d7/EntityTranslationSettings.php
Initializes the iterator with the source data.
FieldInstance::initializeIterator in core/modules/field/src/Plugin/migrate/source/d7/FieldInstance.php
Initializes the iterator with the source data.

... See full list

File

core/modules/migrate/src/Plugin/migrate/source/SqlBase.php, line 251

Class

SqlBase
Sources whose data may be fetched via a database connection.

Namespace

Drupal\migrate\Plugin\migrate\source

Code

protected function initializeIterator() {

  // Initialize the batch size.
  if ($this->batchSize == 0 && isset($this->configuration['batch_size'])) {

    // Valid batch sizes are integers >= 0.
    if (is_int($this->configuration['batch_size']) && $this->configuration['batch_size'] >= 0) {
      $this->batchSize = $this->configuration['batch_size'];
    }
    else {
      throw new MigrateException("batch_size must be greater than or equal to zero");
    }
  }

  // If a batch has run the query is already setup.
  if ($this->batch == 0) {
    $this
      ->prepareQuery();

    // Get the key values, for potential use in joining to the map table.
    $keys = [];

    // The rules for determining what conditions to add to the query are as
    // follows (applying first applicable rule):
    // 1. If the map is joinable, join it. We will want to accept all rows
    //    which are either not in the map, or marked in the map as NEEDS_UPDATE.
    //    Note that if high water fields are in play, we want to accept all rows
    //    above the high water mark in addition to those selected by the map
    //    conditions, so we need to OR them together (but AND with any existing
    //    conditions in the query). So, ultimately the SQL condition will look
    //    like (original conditions) AND (map IS NULL OR map needs update
    //      OR above high water).
    $conditions = $this->query
      ->orConditionGroup();
    $condition_added = FALSE;
    $added_fields = [];
    if ($this
      ->mapJoinable()) {

      // Build the join to the map table. Because the source key could have
      // multiple fields, we need to build things up.
      $count = 1;
      $map_join = '';
      $delimiter = '';
      foreach ($this
        ->getIds() as $field_name => $field_schema) {
        if (isset($field_schema['alias'])) {
          $field_name = $field_schema['alias'] . '.' . $this->query
            ->escapeField($field_name);
        }
        $map_join .= "{$delimiter}{$field_name} = map.sourceid" . $count++;
        $delimiter = ' AND ';
      }
      $alias = $this->query
        ->leftJoin($this->migration
        ->getIdMap()
        ->getQualifiedMapTableName(), 'map', $map_join);
      $conditions
        ->isNull($alias . '.sourceid1');
      $conditions
        ->condition($alias . '.source_row_status', MigrateIdMapInterface::STATUS_NEEDS_UPDATE);
      $condition_added = TRUE;

      // And as long as we have the map table, add its data to the row.
      $n = count($this
        ->getIds());
      for ($count = 1; $count <= $n; $count++) {
        $map_key = 'sourceid' . $count;
        $this->query
          ->addField($alias, $map_key, "migrate_map_{$map_key}");
        $added_fields[] = "{$alias}.{$map_key}";
      }
      if ($n = count($this->migration
        ->getDestinationIds())) {
        for ($count = 1; $count <= $n; $count++) {
          $map_key = 'destid' . $count++;
          $this->query
            ->addField($alias, $map_key, "migrate_map_{$map_key}");
          $added_fields[] = "{$alias}.{$map_key}";
        }
      }
      $this->query
        ->addField($alias, 'source_row_status', 'migrate_map_source_row_status');
      $added_fields[] = "{$alias}.source_row_status";
    }

    // 2. If we are using high water marks, also include rows above the mark.
    //    But, include all rows if the high water mark is not set.
    if ($this
      ->getHighWaterProperty()) {
      $high_water_field = $this
        ->getHighWaterField();
      $high_water = $this
        ->getHighWater();

      // We check against NULL because 0 is an acceptable value for the high
      // water mark.
      if ($high_water !== NULL) {
        $conditions
          ->condition($high_water_field, $high_water, '>');
        $condition_added = TRUE;
      }

      // Always sort by the high water field, to ensure that the first run
      // (before we have a high water value) also has the results in a
      // consistent order.
      $this->query
        ->orderBy($high_water_field);
    }
    if ($condition_added) {
      $this->query
        ->condition($conditions);
    }

    // If the query has a group by, our added fields need it too, to keep the
    // query valid.
    // @see https://dev.mysql.com/doc/refman/5.7/en/group-by-handling.html
    $group_by = $this->query
      ->getGroupBy();
    if ($group_by && $added_fields) {
      foreach ($added_fields as $added_field) {
        $this->query
          ->groupBy($added_field);
      }
    }
  }

  // Download data in batches for performance.
  if ($this->batchSize > 0) {
    $this->query
      ->range($this->batch * $this->batchSize, $this->batchSize);
  }
  $statement = $this->query
    ->execute();
  $statement
    ->setFetchMode(\PDO::FETCH_ASSOC);
  return new \IteratorIterator($statement);
}