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