The first update to the MongoDB 4.2 series, MongoDB 4.2.1, is now available. The new version brings together all the fixes created since version 4.2 went GA. 4.2.1 is a recommended upgrade for all MongoDB 4.2 users.
Details of the fixes in 4.2.1 are in the Release Notes for MongoDB 4.2.
Information on all features of MongoDB is available in the MongoDB 4.2 Manual.
Some of the more noteworthy fixes in 4.2.1 include :
- SERVER-42518: Wildcard index plans miss results when the query path has multiple subsequent array indexes.
- SERVER-42744: Fix transaction history iterator to not return unowned BSON that may be left dangling.
- SERVER-42856: Transactions with write can be sent to the wrong shard.
- SERVER-42946: Setting 4.2 FCV (FeatureCompatibilityVersion) in standalone with existing transaction table crashes MongoDB.
- There's also new platform support with 4.2.1:
All issues addressed in 4.2.1 are listed here.