--- title: "Postgres 19 RC1 and what to test now" publication: "Postgres Weekly" issue: 670 published_at: "2026-10-21" canonical_url: "https://postgresweekly.com/issues/670" --- Plus open-source Citus matches Neki at 10M QPS, DocumentDB reaches 1.0, and does hstore beat jsonb for audit logs? #​670 — October 21, 2026 [Web Version](https://postgresweekly.com/issues/670) Together with [![SerpApi\](https://res.cloudinary.com/cpress/image/upload/c_fill,g_auto,e_trim,w_1280,h_318/e_make_transparent/co_white,e_outline:15/qunbgchsn7czljkekjsk.png)](https://serpapi.com/cooperpress-newsletter) Postgres Weekly [![\](https://res.cloudinary.com/cpress/image/upload/w_1280,e_sharpen:60,q_auto/g1qnzow76mrbuxqpi5rj.jpg)](https://www.enterprisedb.com/blog/postgresql-19-what-changed-what-matters-and-what-test-now) [Postgres 19: What Changed and What to Test Now](https://www.enterprisedb.com/blog/postgresql-19-what-changed-what-matters-and-what-test-now) — With RC1 out and GA due in under a month, Tom Kincaid walks through what survived the reverts and what to try before upgrading, including `REPACK (CONCURRENTLY)`, `pg_plan_advice`, parallel autovacuum, and logical replication sequence synchronization, each with a 'what to test' checklist. Tom Kincaid (EDB) ⭐ [Postgres 19 RC1 was released last week](https://www.postgresql.org/about/news/postgresql-19-rc-1-released-3409/), with an RC2 due November 12 and the final release expected on November 19. [![\](https://res.cloudinary.com/cpress/image/upload/c_limit,w_480,h_480,q_auto/copm/6d11cce3.png)](https://serpapi.com/cooperpress-newsletter) [100+ Search Engines. One Simple API](https://serpapi.com/cooperpress-newsletter) — Add live web search to your backend without managing proxies or parsers. SerpApi delivers structured results from Google and other search engines as clean JSON. SerpApi sponsor [`recovery_prefetch` Considered Harmful and Causing Outages](https://ardentperf.com/2026/10/20/postgres-recovery_prefetch-considered-harmful-and-causing-outages/) — Jeremy shows how `recovery_prefetch`, enabled by default since Postgres 15, can overwhelm standby storage after a write burst, causing hours of lag. With synchronous replication, a dropped connection then blocked primary writes for 35 minutes in [his reproduction.](https://github.com/ardentperf-labs/walreceiver-outage-repro) Jeremy Schneider 🩹 [A patch to avoid redundant prefetches after full-page images](https://www.postgresql.org/message-id/flat/CAAi_3tJsH5UOHLrHJ_YNYC1R-1arg%2BLNoKJPZhaVphPvjhQ%2Bew%40mail.gmail.com) is under review, which tackles part of the problem. **IN BRIEF:** - 🇺🇸 [Postgres Conference 2027](https://postgresconf.org/conferences/2027) takes place April 21–23, 2027 in San Jose, California. If you want to speak, its [CFP is open](https://postgresconf.org/conferences/2027/program/proposals/new) until January 31. - [Who owns an abandoned extension?](https://www.postgresql.org/message-id/flat/952AFDA4-7723-4E88-8263-D0E7792D462C%40justatheory.com) PGXN's David Wheeler asks `pgsql-hackers` what the policy should be, after receiving takeover requests and privilege escalation reports for unmaintained extensions. - 🇧🇪 [FOSDEM PGDay 2027](https://2027.fosdempgday.org/) expands to two days, January 28–29, in Brussels. [The CFP is open](https://2027.fosdempgday.org/callforpapers/) until December 1. - 🇹🇭 [FOSSASIA PGDay 2027](https://eventyay.com/fossasia/pgday2027) takes place on March 9, 2027 in Bangkok. Their [CFP is open](https://eventyay.com/fossasia/pgday2027/cfp) until November 30. - [Neon Realtime](https://neon.com/blog/neon-now-has-realtime) is now in public beta. You can subscribe to any deterministic SQL query and the result stays live as the data changes. - [84% of surveyed Ruby on Rails developers run Postgres in production](https://andyatkinson.com/2026-rails-community-survey-results) as per the results of the 2026 Rails Community Survey. [How `hstore` Can Beat `jsonb` for Audit Logs](https://www.depesz.com/2026/10/16/old-tech-is-sometimes-better-a-case-study-based-on-blogpost-from-now-next/) — depesz saw [a post](https://now-next.nl/en/insights/postgresql-audit-log-per-tenant-trigger-cost/) claiming that logging only changed columns from an audit trigger shrank the log 5x but slowed updates. But his own test, using `hstore` instead of `jsonb`, made diff logging the fastest variant. Hubert 'depesz' Lubaczewski [Why is Postgres's `numeric` Type So Slow?](https://www.pgedge.com/blog/why-is-postgresql-s-numeric-type-so-slow) — A deep dive into `numeric`'s internals explaining why it's slow compared to double precision or DuckDB's integer-backed `DECIMAL`, and why _"just use int128"_ doesn't fix it. Andrei Lepikhov (pgEdge) [Citus Hits 10M QPS on Half _Neki_'s Data Nodes](https://stackgres.io/blog/open-source-citus-matches-planetscales-neki-at-10m-qps-on-half-the-data-nodes/) — A month after PlanetScale's [118M QPS Neki post](https://planetscale.com/blog/118-million-queries-per-second-on-neki), Álvaro ran the same shape of workload on Citus with StackGres's new query routers and hit 10M QPS on 24 workers rather than Neki's 50 shards. Álvaro Hernández (StackGres) 🎧 [Postgres FM had Álvaro on the same day](https://postgres.fm/episodes/citus-stackgres) for an hour on Citus, StackGres and the thinking behind the benchmark. 📄 [Why Materialize Dropped `SERIALIZABLE` for 3x Write Throughput](https://materialize.com/blog/building-a-linearizable-log-on-read-committed) – Hundreds of thousands of predicate locks sank their Postgres-backed metadata store, so they rebuilt it on `READ COMMITTED` and _proved_ it correct in Lean. Petros Angelatos 📄 [From Alert to Online Repack: A Playbook for Postgres Table Bloat](https://techcommunity.microsoft.com/t5/microsoft-blog-for-postgresql/from-alert-to-online-repack-playbook-for-postgresql-table-bloat/ba-p/4562659) – Build a bloat 'watchdog' with `pg_cron` and `pgstattuple`, then use `pg_repack` to take a 13GB table down to 3.4GB without taking it offline. Haider Z (Microsoft) 📄 [Reducing Storage Initialization Impact in Amazon RDS After Snapshot Restore](https://aws.amazon.com/blogs/database/reducing-storage-initialization-impact-in-amazon-rds-for-postgresql-after-snapshot-restore/) – Why queries on a freshly restored RDS Postgres can run 10–15x slower at first, and how to prewarm it. Modappady, Pattabiraman and Thakur (AWS) 📄 [UUIDs Stored as `text`: What It Costs in Postgres 18](https://explainmeasured.com/posts/uuid-as-text/) Hollis Varden 📰 Classifieds Today: Let a coding agent fork, break, and fix a real Postgres database. [Free live workshop](https://www.tigerdata.com/events/workshop-tiger-mcp?utm_source=content-syndication&utm_medium=referral&utm_campaign=postgres-weekly-newsletter), recording included. **RELEASES AND CODE:** [![\](https://res.cloudinary.com/cpress/image/upload/w_1280,e_sharpen:60,q_auto/sv56ilc9yxghvv6sdnem.jpg)](https://documentdb.io/blogs/posts/documentdb-1-0/) [DocumentDB 1.0: A MongoDB-Compatible Document Database on Postgres](https://documentdb.io/blogs/posts/documentdb-1-0/) — First open sourced by Microsoft last year but now a Linux Foundation project, DocumentDB is a set of extensions (plus a gateway) that speak the MongoDB wire protocol and store BSON natively. This first stable release comes with packages for Postgres 17 and 18. DocumentDB [PGX: Run Thousands of Throwaway Databases in One Process](https://pgx.dev/) — From the team behind [pgbot](https://github.com/pgrundev/pgbot), and built upon a Rust reimplementation of Postgres, PGX hosts large numbers of isolated databases in one process, each cloned from a template in milliseconds, for agent sandboxes and per-PR tests. Beta, AGPL-licensed, with `fsync` off, so for dev use only. ([GitHub repo](https://github.com/pgrundev/pgx).) PGRun [pgBackRest 2.60: Restores Now Stop on Invalid Page Checksums](https://pgbackrest.org/release.html#2.60.0) — The popular backup and restore tool now stops a restore with an error if any restored file has an invalid page checksum. Worth knowing before your next restore! (`checksum-page-error=n` can change it to a warning only.) pgBackRest Community - [pg_hint_plan 1.9.0](https://github.com/ossc-db/pg_hint_plan/releases/tag/REL19_1_9_0) – The long-standing query hinting extension, now built (only) for Postgres 19 using its new path generation strategies. - [PostgREST 16.5](https://github.com/PostgREST/postgrest/releases/tag/v16.5) – Popular REST API server layer for Postgres. Adds a client-side mitigation for a recent Postgres CVE. - ⚠️ [pgmq 1.13.1](https://github.com/pgmq/pgmq/releases/tag/v1.13.1) – The Postgres-native message queue. Fixes two privilege issues, so upgrade if you use it. - [pg_ivm 1.17](https://github.com/sraoss/pg_ivm/releases/tag/v1.17) – Incrementally maintained materialized views, which can now survive`pg_upgrade` if you use `pg_ivm_dump_metadata --pg-upgrade`. - 🌐 [PostGIS 3.7.0 RC3](https://postgis.net/2026/10/PostGIS-3.7.0rc3/) – The geospatial data extension targets Postgres 19 RC1 – I'd expect a final 3.7 around the same time as Postgres 19 itself. **Got a new email?** You can [change your address here](https://postgresweekly.com/edit_subscription/*|UID|*). --- **Bored of us?** [Click here to stop getting Postgres Weekly](https://postgresweekly.com/leave/*|UID|*). --- **Got a link for us?** Reply and tell us. We can't include everything but we'll look at anything you send. _Thanks!_ --- Published by Cooper Press Ltd. 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