mongominkey(3) [php man page]

MONGOMINKEY(3)								 1							    MONGOMINKEY(3)

The MongoMinKey class

INTRODUCTION

       MongoMinKey is an special type used by the database that compares less than all other possible BSON values. Thus, if a query is sorted by a
       given field in ascending order, any document with a MongoMinKey as its value will be returned first.

       MongoMinKey has no associated fields, methods, or constants. It is merely the "smallest" value that can be represented in the database.

       Note

	      MongoMinKey is used internally by MongoDB for indexing and sharding. There is generally no reason to use this class in  an  applica-
	      tion.

CLASS SYNOPSIS

       MongoMinKey

       MongoMinKey

USING  MongoMinKey"; AS A VALUE"
       <?php

       $collection->insert(array("task" => "lunch", "doBy" => new MongoMinKey));
       $collection->insert(array("task" => "staff meeting", "doBy" => new MongoDate(strtotime("+4 days"))));

       $cursor = $collection->find()->sort(array("doBy" => 1));

       ?>

	The  cursor  will  return  the	lunch  document  followed by the staff meeting document. The lunch document will always be returned first,
       regardless of what else is added to the collection (unless other documents are added with MongoMinKey in their "doBy" field).  See Also

	      oMongoMaxKey

PHP Documentation Group 													    MONGOMINKEY(3)

MONGOCURSOR(3)								 1							    MONGOCURSOR(3)

The MongoCursor class

INTRODUCTION

	A cursor is used to iterate through the results of a database query. For example, to query the database and see all results, you could do:

       Example #1

	      MongoCursor basic usage

	      <?php

	      $cursor = $collection->find();
	      var_dump(iterator_to_array($cursor));

	      ?>

	You  don't  generally  create cursors using the MongoCursor constructor, you get a new cursor by calling MongoCollection.find(3) (as shown
       above).

	Suppose that, in the example above, $collection was a 50GB collection. We certainly wouldn't want to load that into memory  all  at  once,
       which is what a cursor is for: allowing the client to access the collection in dribs and drabs.

	If  we have a large result set, we can iterate through it, loading a few megabytes of results into memory at a time. For example, we could
       do:

       Example #2

	      Iterating over MongoCursor

	      <?php

	      $cursor = $collection->find();

	      foreach ($cursor as $doc) {
		  // do something to each document
	      }

	      ?>
	This will go through each document in the collection, loading and garbage collecting documents as needed.

	Note that this means that a cursor does not "contain" the database results, it just manages them. Thus, if you print a cursor (with,  say,
       var_dump(3)  or print_r(3)), you'll just get the cursor object, not your documents. To get the documents themselves, you can use one of the
       methods shown above.

CURSOR STAGES

	A MongoCursor has two "life stages": pre- and post- query. When a cursor is created, it has not yet contacted the database, so	it  is	in
       its  pre-query  state. In this state, the client can further specify what they want the query to do, including adding limits, skips, sorts,
       and more advanced options.

	When the client attempts to get a result (by calling MongoCursor.next(3), directly or indirectly), the cursor moves  into  the	post-query
       stage. At this point, the query has been executed by the database and cannot be modified anymore.

       Example #3

	      Adding options to MongoCursor

	      <?php

	      $cursor = $collection->find()->limit(10);

	      // database has not yet been queried, so more search options can be added
	      $cursor = $cursor->sort(array("a" => 1));

	      var_dump($cursor->getNext());
	      // now database has been queried and more options cannot be added

	      // so this will throw an exception:
	      $cursor->skip(4);
	      ?>

CLASS SYNOPSIS

       MongoCursor

       MongoCursorMongoCursorInterfaceIterator

       Static Fields

       o static boolean$slaveOkay FALSE

       o static integer$timeout30000

       Methods

       o public MongoCursor MongoCursor::addOption (string  $key, mixed  $value)

       o public MongoCursor MongoCursor::awaitData ([bool  $wait = true])

       o public MongoCursor MongoCursor::batchSize (int  $batchSize)

       o public MongoCursor::__construct (MongoClient  $connection, string  $ns, [array  $query = array()], [array  $fields = array()])

       o public int MongoCursor::count FALSE ([bool  $foundOnly])

       o public array MongoCursor::current (void  )

       o public bool MongoCursor::dead (void  )

       o protected void MongoCursor::doQuery (void  )

       o public array MongoCursor::explain (void  )

       o public MongoCursor MongoCursor::fields (array	$f)

       o public array MongoCursor::getNext (void  )

       o public array MongoCursor::getReadPreference (void  )

       o public bool MongoCursor::hasNext (void  )

       o public MongoCursor MongoCursor::hint (mixed  $index)

       o public MongoCursor MongoCursor::immortal ([bool  $liveForever = true])

       o public array MongoCursor::info (void  )

       o public string|int MongoCursor::key (void  )

       o public MongoCursor MongoCursor::limit (int  $num)

       o public MongoCursor MongoCursor::maxTimeMS (int  $ms)

       o public array MongoCursor::next (void  )

       o public MongoCursor MongoCursor::partial ([bool  $okay = true])

       o public void MongoCursor::reset (void  )

       o public void MongoCursor::rewind (void	)

       o public MongoCursor MongoCursor::setFlag (int  $flag, [bool  $set = true])

       o public MongoCursor MongoCursor::setReadPreference (string  $read_preference, [array  $tags])

       o public MongoCursor MongoCursor::skip (int  $num)

       o public MongoCursor MongoCursor::slaveOkay ([bool  $okay = true])

       o public MongoCursor MongoCursor::snapshot (void  )

       o public MongoCursor MongoCursor::sort (array  $fields)

       o public MongoCursor MongoCursor::tailable ([bool  $tail = true])

       o public MongoCursor MongoCursor::timeout (int  $ms)

       o public bool MongoCursor::valid (void  )

STATIC VARIABLES

	      o $slaveOkay
		-  If  the  query should have the "slaveOkay" flag set, which allows reads on the secondary (secondaries are, by default, just for
		backup and not queried). Can be overridden with MongoCursor.slaveOkay(3).  This functionality  is  deprecated.	Please	use  "Read
		Preferences" instead.

	      o $timeout
		-  Set	timeout in milliseconds for all database responses. Use -1 to wait forever. Can be overridden with MongoCursor.timeout(3).
		This does not cause the MongoDB server to cancel the operation; it only instructs the driver to stop waiting for  a  response  and
		throw a MongoCursorTimeoutException after a set time.

SEE ALSO

	MongoDB core docs on cursors.

PHP Documentation Group 													    MONGOCURSOR(3)