You usually do not instantiate BatchQueryResult directly. Instead, you obtain it by
calling [[Query::batch()]] or [[Query::each()]]. Because BatchQueryResult implements the Iterator interface,
you can iterate it to obtain a batch of data in each iteration. For example,
php
$query = (new Query())->from('user');
foreach ($query->batch() as $i => $users) {
$users represents the rows in the $i-th batch
}
foreach ($query->each() as $user) {
}
/**
* Starts a batch query and retrieves data row by row.
* This method is similar to [[batch()]] except that in each iteration of the result,
* only one row of data is returned. For example,
*
* ```php
* $query = (new Query)->from('user');
* foreach ($query->each() as $row) {
* }
* ```
*
* @param int $batchSize the number of records to be fetched in each batch.
* @param Connection $db the MongoDB connection. If not set, the "mongodb" application component will be used.
* @return BatchQueryResult the batch query result. It implements the `Iterator` interface
* and can be traversed to retrieve the data in batches.
* @since 2.1
*/
public function each($batchSize = 100, $db = null)
{
return Yii::createObject(['class' => BatchQueryResult::className(), 'query' => $this, 'batchSize' => $batchSize, 'db' => $db, 'each' => true]);
}
