Release Notes for MongoDB 7.2

7.2.2 - Feb 28, 2024

Issues Fixed:

• SERVER-84723 Sharded multi-document transactions can observe partial effects of concurrent DDL operations

• All JIRA issues closed in 7.2.2

• 7.2.2 Changelog

7.2.1 - Feb 27, 2024

Issues fixed:

• SERVER-72703 Downgrade $out's db lock to MODE_IX

• SERVER-80363 server default writeConcern is not honored when wtimeout is set

• SERVER-83492 Remove limit and skip values from SBE plan cache key if possible

• SERVER-84013 Incorrect results for index scan plan on query with duplicate predicates in nested $or

• SERVER-84338 Top level $or queries may lead to invalid SBE plan cache entry which returns wrong results

• All JIRA issues closed in 7.2.1

• 7.2.1 Changelog

Database Validation on mongos Aggregation Queries

Starting in MongoDB 7.2, aggregation pipeline queries that attempt to use non-existent databases on mongos deployments return validation errors.

In previous versions, these aggregation queries return empty cursors.

serverStatus Metrics

Starting in MongoDB 7.2, the serverStatus command and the db.serverStatus() method outputs include the following new metrics:

• metrics.operation.killedDueToMaxTimeMSExpired

• readPreferenceCounters

getField Field Supports All Strings

Starting in MongoDB 7.2, you can specify any valid expression that resolves to a string for the field input of the $getField operator. In earlier versions, field accepts only string constants.

Default Chunks Per Shard

Starting in MongoDB 7.2, when you shard an empty collection with a hashed shard key, the operation creates one chunk per shard by default. Previously, the operation created two chunks by default.