November 9, 2021 | Updated: June 3, 2022
Arriving just a few months after the General Availability of 5.0, MongoDB 5.1 is our first Rapid Release which brings more native time series enhancements, richer analytics, new security options, and overall improvements to platform resilience and developer productivity. Launching alongside MongoDB 5.1 are new capabilities in Atlas Search which will make it easier for users to build fast and rich application search experiences.
MongoDB 5.1 marks our accelerated release cadence designed to get new database features and improvements into your hands faster than ever before. MongoDB 5.1 and all future rapid releases will be fully supported on MongoDB Atlas and are available as development releases from our Download Center.
Native Time Series Enhancements
With optimized time series collections, clustered indexes, and window functions, MongoDB 5.0 made it faster, easier, and lower cost to serve the industry’s fastest growing, data intensive use cases such as IoT platforms and real-time financial analytics. Now with MongoDB 5.1, you can globally distribute your time series applications and further simplify their development:
More developer velocity
Time series collections can now take advantage of MongoDB’s native sharding to horizontally distribute massive data sets and co-locate nodes with data producers to support local write operations and to enforce the data sovereignty controls.
It is common for time series data to be uneven, for example a sensor goes offline and several readings are missed. But in order to perform analytics and ensure correctness of results data needs to be continuous. With densification you can now handle missing data better and build time series apps and analytics faster putting less burden on the developer. Time series collections now also support delete operations. While most time series applications are append-only, users need to be able to invoke their right to erasure so we are giving developers an easy way to comply with modern data privacy regulations.
Complete data lifecycle
From medical sensors to market data fluctuations, time series means hundreds of millions data points per day. You need to process these massive volumes fast, distill valuable insights then continue to retain the full data set for regulatory purposes - possibly for years - all without incurring skyrocketing costs and data movement complexity. With Atlas Online Archive support for time series, now available in preview, you can do exactly that and seamlessly and economically manage your entire time series data lifecycle. Simply define your own archiving policy, and Atlas handles all data movement for you by tiering aged time series data out of your database into lower cost, fully managed cloud object storage. Rather than delete anything, you can retain all your time series data, preserving the ability to query it at any time alongside your live data for long term trend analytics and machine learning, or for compliance purposes. Support for online archiving is available for MongoDB 5.0 and above.
Broader platform support for Time Series Data
Our native time series capabilities are supported across the entire MongoDB data platform making it easy to work with time series data in any context. You can now create time series collections directly from Atlas Data Explorer, MongoDB Compass or MongoDB for VS Code. With support for date binning, date filtering options, and value comparison, Atlas Charts lets you create graphs and dashboards from any Atlas times series collection, easily share insights, and embed visualizations into your applications for a rich user experience.
Richer and More Flexible Analytics and Full-Text Search
Many developers start out with MongoDB for their operational use cases, and then expand to leverage our platform's versatility in powering analytics and search as well. MongoDB 5.1 includes new features and enhancements that make it easier to unlock insights from your data and improve user experience.
Cross-shard joins and graph traversals
For most transactional and operational workloads, the document data model largely eliminates the need to join data from different collections. This is because related data can be embedded in sub-documents and arrays within a single, richly structured document – following the principle that what is accessed together is often best stored together.
However analytical applications can sometimes require joins to be executed – for example bringing together customers and orders from separate collections. Through the $lookup aggregation pipeline stage, you can have the database join collections for you. The $graphLookup stage gives you the ability to traverse related data, performing “friend-of-friend” type queries to uncover patterns and surface previously unidentified connections in your data.
In MongoDB 5.1 we now allow you to use $lookup and $graphLookup to combine and analyze data that is distributed across shards which was not previously possible. Our design gives you even more precision in your code by enabling you to target individual shards as needed. However you don’t need to understand sharding or even know your collection is sharded to run these queries as there is no new syntax for developers to learn.
Materializing results for operational analytics
The $merge and $out aggregation stages can be used to write the results of an aggregation pipeline in order to create a new collection or create/update an on-demand materialized view. These stages enable users to reduce processing overhead by reading pre-computed results instead of re-running the aggregation each time, and by writing only incremental results when the aggregation results change.
Users often want to run resource-intensive analytical queries on secondary nodes in order to avoid performance impacts on the primary — but since only primaries can serve writes, aggregations including $out or $merge could not previously run on a secondary node.
Soon, such pipelines will run, performing their query execution work on a secondary node, then automatically directing any writes to the primary. This allows you to offload computationally expensive analytics work to secondary nodes while still being able to materialize the results of that work. This will be accessible via drivers in their upcoming releases.
Full-Text Search Facets: now in public preview
Faceted search allows users to filter and quickly navigate search results by categories and see the total number of results per category for at-a-glance statistics. With our new facet operator, facet and count operations are pushed down into Atlas Search’s embedded Lucene index and processed locally, taking advantage of 20+ years of Lucene optimizations. This makes workloads such as ecommerce product catalogs, content libraries, and counts run up to 100x faster. Learn more from our Atlas Search facets blog post.
New and Enhanced Security Options
End-to-end encryption for confidential computing
Extending beyond cloud provider Key Management Services (KMS), MongoDB’s unique Client-Side Field Level Encryption will support any KMIP-compliant KMS. This functionality is being released in new versions of drivers that will be available soon.
Client-Side FLE delivers some of the strongest privacy and security controls available anywhere today. By using the MongoDB drivers to encrypt the most sensitive fields in your documents before they leave the application you can do three things that are not possible with in-flight or at-rest encryption alone:
Protect data while it is in-use, in the memory of your active database instance. The database never sees plaintext, but data remains queryable.
Make data unreadable to anyone running the database for you, or who has access to the underlying database infrastructure — this includes MongoDB SREs running the Atlas services as well as cloud provider personnel.
Simplify the process of enforcing right to erasure (sometimes called right to be forgotten) mandates in modern privacy regulations such as the GDPR or the CCPA. This is because you simply destroy the key encrypting a user’s PII, and their data is rendered unreadable and unrecoverable — in-memory, at-rest, in backups, and in logs.
Google Cloud Private Service Connect
We’ve also added a new network security option to MongoDB Atlas with the availability of Google Private Service Connect (PSC). Private Service Connect allows you to create private and secure connections from your Google Cloud networks to MongoDB Atlas. It creates service endpoints in your VPCs that provide private connectivity and policy enforcement, allowing you to easily control network security in one place.
Along with VPC Peering, Google Cloud PSC makes it easy to connect your applications and services in Google Cloud to Atlas.
MongoDB 5.1 continues to build out controls for reliability and availability with the following enhancements:
We've made a number of changes to WiredTiger internals that improve backups, including minimizing the checkpoints pinned while a backup cursor is open and improving handling of backup cursors that are open for long periods. These improvements will reduce both the operational overhead and storage consumption on the replica node from which the backup is taken. This improvement is available for backups taken from MongoDB Atlas and from self-hosted deployments controlled by Ops Manager or Cloud Manager, and has been backported to MongoDB 4.2 and above.
In addition to enhancements affecting backups, WiredTiger checkpointing and locking have been improved to enhance performance when MongoDB is managing many concurrently active collections in a single instance. This is especially useful to multi-tenant applications built on MongoDB.
We'll also be adding improvements in upcoming versions of our drivers that support mongos controls to mitigate connection storms in sharded clusters, especially during failover events. These include preferentially connecting to nodes that have existing idle connections that can be reused, improving the matching of connection pool sizing across replica set members, limiting the rate of new connections, and adding a mechanism to limit the number of mongos servers used when connecting to sharded clusters via SRV records.
Improved Productivity for C# Developers
Making it easier for developers to query and manipulate data is at the core of our mission. For C# developers the LINQ API serves as the main gateway between the language and database. In MongoDB 5.1 we are improving developer productivity for our C# community with a completely redesigned LINQ interface that lets developers write all of their MongoDB queries as well as build sophisticated aggregation pipelines natively in C#.
Getting Started with MongoDB 5.1
You can learn more about all of the new features and enhancements in MongoDB 5.0 and 5.1 from our Guide to What’s New.
MongoDB 5.1 is available now. If you are running Atlas Serverless instances or have opted in to receive Rapid Releases in your dedicated Atlas cluster, then your deployment will be automatically updated to 5.1 starting today. For a short period after upgrade, the Feature Compatibility Version (FCV) will be set to 5.0; certain 5.1 features will not be available until we increment the FCV. MongoDB 5.1 is also available as a Development Release for evaluation purposes only from the MongoDB Download Center. Consistent with our new release cadence announced last year, the functionality available in 5.1 and the subsequent Rapid Releases will all roll up into MongoDB 6.0, our next Major Release scheduled for delivery in 2022.
I really look forward to hearing what you think about MongoDB 5.1, and can’t wait to tell you what’s new in the 5.2 Rapid Release scheduled for next quarter.
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