* Query planner improvements (aggregates, incremental sorts, etc)
* Large performance gains in bulk loading (COPY)
* vacuum improvements
* logical replication - start of bi-directional foundation, logical repl from standby
* pg_stat_io
* large connection count improvements
* in-memory/on-disk sorting improvements
* logical replication - specify column lists/row filters
* WAL compression options
* partition table performance fixes
* note: Public schema permissions change with this release
* large connection count improvements
* indexing data structure improvements
* query parallelism improvements
* vacuum performance improvements
* Stored procedures can now return data via OUT parameters.
* Improved performance for aggregates or partitioned tables
* Space savings and performance gains in B-tree indexes
* Extended statistics for query planning
* Parallelized vacuuming of indexes
* Incremental sorting
* Support for SQL/JSON path language
* B-tree indexes performance improvements, rebuild indexes concurrently.
* Inline common table expressions
* General performance improvements
* Enhancements to administrative functionality(REINDEX CONCURRENTLY, pg_checksums Progress reporting statistics)
* Support for the SQL/JSON path language
* Stored generated columns
* New authentication features
* Improvements to partitioning functionality
* Improvements to parallelism, including:
* SQL stored procedures that support embedded transactions
* Optional Just-in-Time (JIT) compilation for some SQL code, speeding evaluation of expressions
* Covering indexes can now be created, using the INCLUDE clause of CREATE INDEX
* Logical replication using publish/subscribe
* Declarative table partitioning
* Improved query parallelism
* Significant general performance improvements
* Stronger password authentication based on SCRAM-SHA-256
* Improved monitoring and control
* Parallel execution of sequential scans, joins and aggregates
* Avoid scanning pages unnecessarily during vacuum freeze operations
* Synchronous replication now allows multiple standby servers for increased reliability
* Full-text search can now search for phrases (multiple adjacent words)
* postgres_fdw now supports remote joins, sorts, UPDATEs, and DELETEs
* Substantial performance improvements, especially in the area of scalability on multi-CPU-socket servers
* Allow INSERTs that would generate constraint conflicts to be turned into UPDATEs or ignored
* Add GROUP BY analysis features GROUPING SETS, CUBE and ROLLUP
* Add row-level security control
* Create mechanisms for tracking the progress of replication, including methods for identifying the origin of individual changes during logical replication
* Add Block Range Indexes (BRIN)
* Substantial performance improvements for sorting
* Substantial performance improvements for multi-CPU machines
* Add jsonb, a more capable and efficient data type for storing JSON data
* Add new SQL command ALTER SYSTEM for changing postgresql.conf configuration file entries
* Reduce lock strength for some ALTER TABLE commands
* Allow materialized views to be refreshed without blocking concurrent reads
* Add support for logical decoding of WAL data, to allow database changes to be streamed out in a customizable format
* Allow background worker processes to be dynamically registered, started and terminated