We continue to follow the news about PostgreSQL 18. The January CommitFest brings in some notable improvements to monitoring, as well as other new features.

You can find previous reviews of PostgreSQL 18 CommitFests here: 2024-07, 2024-09, 2024-11.

EXPLAIN (analyze): buffers on by defaultpg_stat_io: input/output statistics in bytes instead of pagespg_stat_io: WAL statisticspg_stat_get_backend_io: I/O statistics for a specific processVACUUM(verbose): visibility map informationTotal vacuum and analysis time per tableautovacuum: change the number of workers without restarting the serverpsql: connection service informationpsql: expanded display for \d* commandspsql: leakproof flag in \df* outputjsonb: null conversion to other typesMD5 encryption algorithm: end-of-support preparationsNew function uuidv7postgres_fdw: SCRAM authentication without storing the passwordpasswordcheck: minimum password lengthNew function casefold and pg_unicode_fast collationDML commands: RETURNING with OLD and NEWto_number: convert a string of roman numberals to numeric

We continue the series of articles about new patches coming to PostgreSQL 18, this one covering the news of the November CommitFest.

If you missed the previous reviews, you can check them out here: 2024-07, 2024-09.

• initdb: checksum calculation enabled by default
• Planner: array lookup instead of multiple similar conditions under OR
• Planner: switching around expressions in DISTINCT clauses
• GROUPING SETS: HAVING -> WHERE
• Data type cache entry invalidation and temporary tables
• Planner: incremental sorting during Merge Join
• New function array_reverse
• Functions min and max for the type bytea
• Parallel worker usage statistics
• New function pg_ls_summariesdir
• new contrib module: pg_logicalsnapinspect
• Improved extension installation error messages
• NOT NULL constraints in the system catalog
• A TOAST table for pg_index
• COPY... FROM and file_fdw: rejected row limit
• LIKE support with nondetermenistic collations
• TLS v1.3: cipher suites

Statistically, September CommitFests feature the fewest commits. Apparently, the version 18 CommitFest is an outlier. There are many accepted patches and many interesting new features to talk about.

If you missed the July CommitFest, get up to speed here: 2024-07.

• Conflict detection and logging in logical replication
• Planner: no more 10000000000
• Planner: memory management and usage monitoring for temporary tuple storage
• Reading buffers during index backwards scan
• pg_upgrade: asynchronous operations in multiple databases
• Hash Join speed-up
• Faster text value processing in JSON
• Optimized numeric-type multiplication
• Optimized numeric-type division
• ANALYZE ONLY and VACUUM ONLY
• Improved checkpointer statistics
• pg_stat_statements: normalization of SET commands
• postgres_fdw_get_connections and remote connection status
• file_fdw: ignore format conversion errors
• New function has_largeobject_privilege
• Functions crc32 and crc32c
• Client-server protocol: report search_path changes to the client
• psql: support for named prepared statements
• pg_verifybackup: integrity verification for tar backups