Warning
MongoDB 9.0 Not Yet Available
MongoDB 9.0 release candidates are not yet available. This version of the manual is for an upcoming release and is currently a work in progress.
General Changes
Change Stream Pre-Image Metrics
Starting in MongoDB 9.0, the
changeStreamPreImages.purgingJob.docsDeleted and
changeStreamPreImages.purgingJob.bytesDeleted serverStatus metrics
may report estimates rather than exact values. These estimates occur
when size and count information is not available for the
config.system.preimages collection. For details, see
changeStreamPreImages.
Server-side JavaScript
Starting in MongoDB 9.0, the server-side JavaScript functions
($accumulator, $function, and $where)
are no longer deprecated. MongoDB 9.0 re-enables these functions using a
WebAssembly (WASM)-based JavaScript engine, which improves security
through stronger sandboxing and isolation than prior versions. These
functions were previously deprecated in MongoDB 8.0. To learn more, see
Server-side JavaScript.
Server Status
MongoDB 9.0 adds the following serverStatus metrics:
Cursor Namespace in Command Responses
Starting in MongoDB 9.0, when you run a find, aggregate, or listIndexes
command on a time series collection, the cursor.ns field in the
response returns the user-facing namespace you originally targeted. In previous
versions, the server could return the internal namespace.
Time Series
renameCollection
Starting in MongoDB 9.0, you can rename time series collections with
renameCollection.
Aggregation
$queryStats Output
MongoDB 9.0 updates the $queryStats output to streamline metrics
organization. This update includes the following new output fields:
Field | Description |
|---|---|
| A document that contains metrics relevant to the cursor and batching protocol |
| A document that contains metrics relevant to query execution |
| A document that contains metrics relevant to the query planner |
| A document that contains metrics relevant to operation writes |
For more information on the new output structure, see $queryStats Output.
Security
useInternalAuthzForX509 Parameter
MongoDB 9.0 adds the useInternalAuthzForX509
parameter. When set to true, clients that authenticate
using MONGODB-X509 use internal authorization,
even when LDAP authorization is configured. For details, see
useInternalAuthzForX509.
usersInfo authenticatedMechanism Field
MongoDB 9.0 adds the authenticatedMechanism field to the
usersInfo command. This optional string field
specifies an authentication mechanism to determine which
authorization backend usersInfo queries when looking up
user authorization information. For details, see
usersInfo.