Release 0.201

System memory pool is now unused by default and it will eventually be removed completely. All memory allocations will now be served from the general/user memory pool. The old behavior can be restored with the deprecated.legacy-system-pool-enabled config option.
Improve performance and memory usage for queries using row_number() followed by a filter on the row numbers generated.
Improve performance of queries that process structural types and contain joins, aggregations, or table writes.
Add session property prefer-partial-aggregation to allow users to disable partial aggregations for queries that do not benefit.

Change rules in the for enforcing matches between authentication credentials and a chosen username to allow more fine-grained control and ability to define superuser-like credentials.

Change ORC writer validation configuration hive.orc.writer.validate to switch to a sampling percentage hive.orc.writer.validation-percentage.
Fix optimized ORC writer writing incorrect data of type map or array.
Fix and the $partitions table for tables that have null partition values.