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(PECL mongo >=1.5.0)
MongoCollection::parallelCollectionScan — Returns an array of cursors to iterator over a full collection in parallel
$num_cursors
)This method returns an array of a maximum of num_cursors cursors. An iteration over one of the returned cursors results in a partial set of documents for a collection. Iteration over all the returned cursors results in getting every document back from the collection.
This method is a wrapper for the parallelCollectionScan MongoDB command.
num_cursors
The number of cursors to request from the server. Please note, that the server can return less cursors than you requested.
Returns an array of MongoCommandCursor objects.
Example #1 MongoCollection::parallelCollectionScan() example
Returning all documents in a collection by using multiple cursors.
<?php
$m = new MongoClient ;
$c = $m -> demo -> cities ;
$cursors = $c -> parallelCollectionScan ( 3 );
$mi = new MultipleIterator ( MultipleIterator :: MIT_NEED_ANY );
foreach ( $cursors as $cursor )
{
$mi -> attachIterator ( $cursor );
}
foreach ( $mi as $items )
{
foreach ( $items as $item )
{
if ( $item !== NULL )
{
echo $item [ 'name' ], "\n" ;
}
}
}
?>