&ChangelogListingDescription; It supports all new features for MongoDB 2.6, including: Aggregate can now return a cursor Aggregation pipelines can now be explained Possible to set maxTimeMS for commands and queries Transparent support for the new command-based MongoDB write API New MongoWriteBatch classes (using the new MongoDB write API) Support for MongoDB Enterprise features (e.g. Kerberos, LDAP, X509) Option to tune acceptable server latency for secondary reads (secondaryAcceptableLatencyMS) With this release, some driver functionality which was previously documented as deprecated will now formally raise deprecation notices. This includes: Instantiating the Mongo class Calling MongoCursor::slaveOkay() "wtimeout" and "safe" options for MongoCollection write operations Manipulating public properties on core classes (such as $collection->w) No previously deprecated features have been removed. Changes in behaviour: Setting the mongo.native_long INI setting now raises an error on 32-bit platforms, and now defaults to true for 64-bit platforms. The 1.4 series introduced fundemental changes in how connections are created to the MongoDB servers. The driver now utilizes PHP native streams, so all normal PHP stream options apply. Furthermore, an experimental Stream Context Support was added. The 1.4.x series also added support for MongoDB 2.4.x. The most important improvements however deal with the handling of replica sets, especially nodes that timeout and nodes that are unreachable for various reasons. Besides the improvements to replica set handling, this release addresses issues with read preferences through mongos nodes. It also adds support for SSL enabled connections as well as journal and fsync connection string options. The 1.3 series introduced several major changes to the extension such as completely rewritten connection handling (and removal of the pooling mechanism), support for ReadPreferences and change the default WriteConcerns to be acknowledged by introducing a new class MongoClient which serves as a replacement class for the now deprecated Mongo class. The driver now also supports connecting to multiple mongos instances (the Mongo Shard router) for loadbalancing. Other enhancements include improved logging for easier connection handling debugging with MongoLog and support for the Aggregation Framework via the MongoCollection::aggregate method. Following is a list of all improvements to existing methods since their inception.