Amazon DocumentDB (with MongoDB compatibility) adds six new aggregation operators and improved indexing capabilities

Amazon DocumentDB (with MongoDB compatibility) is a fast, scalable, highly available, and fully managed document database service that supports MongoDB workloads. Amazon DocumentDB makes it easy and intuitive to store, query, and index JSON data.

Amazon DocumentDB continues to increase compatibility with MongoDB and today added additional capabilities for the MongoDB 3.6 compatible database engine:

• Aggregation Operators – We have added support for new aggregation operators: $ifNull, $replaceRoot, $setIsSubset, $setInstersection, $setUnion, and $setEquals.
• Performance and indexing – Included in this release are multiple performance and indexing improvements: the ability to use an index with the $lookup aggregation stage, find() queries with projections can be served direction from an index (covered query), the ability to use hint() with the findAndModify API, performance optimizations for $addToSet operator, and improvements to reduce overall index sizes.
• Monitoring - Three new CloudWatch metrics to monitor resource utilization - LowMemNumOperationsThrottled, LowMemThrottleMaxQueueDepth, and LowMemThrottleQueueDepth

To learn more about Amazon DocumentDB see the product page and documentation. To get started with Amazon DocumentDB, see the following tutorial.