PostgreSQL on Vonng

PIGSTY

rh@vonng.com (Ruohang Feng) — Sat, 11 Jul 2026 00:00:00 +0000

Release notes for Pigsty, the open-source PostgreSQL RDS distribution

Did AI Rewrite PostgreSQL in Rust? Not Quite

rh@vonng.com (Ruohang Feng) — Sat, 11 Jul 2026 00:00:00 +0000

pgrust’s clean-room rewrite failed. Its mechanical port passed. The difference shows what AI can copy—and what it cannot.

Happy 30th Birthday, PostgreSQL

rh@vonng.com (Ruohang Feng) — Wed, 08 Jul 2026 00:00:00 +0000

On July 8, 1996, the PostgreSQL community picked up the flame from Postgres95. Thirty years later, it has grown from a Berkeley research project into a default foundation of the global database ecosystem.

Instantly Clone PostgreSQL Databases—No Black Magic Required

rh@vonng.com (Ruohang Feng) — Mon, 06 Jul 2026 00:00:00 +0000

Pig v1.5 adds pig pg clone and pig pg fork, wrapping PostgreSQL 18’s instant cloning capabilities in an agent-native CLI.

What Is a PostgreSQL Distribution?

rh@vonng.com (Ruohang Feng) — Sat, 04 Jul 2026 00:00:00 +0000

Starting with Linux distributions, this essay explains what a “PostgreSQL distribution” actually is: three layers, two paths, and one core idea.

Fifty Years of Love and War: File Systems, Databases, and the Agent-Era Storage Endgame

rh@vonng.com (Ruohang Feng) — Fri, 03 Jul 2026 00:00:00 +0000

File systems and databases have spent fifty years fighting and borrowing from each other. The agent era may seem to put file systems back on top, but the real winner may be databases that learn to speak the file system’s dialect: models provide understanding, databases provide guarantees, and discovery comes from a protocol layer where ls works on everything.

Extensions for Everyone

rh@vonng.com (Ruohang Feng) — Wed, 20 May 2026 00:00:00 +0000

A field report on the PostgreSQL extension ecosystem: 1,617 discovered projects, 511 deliverable extensions, and the shared delivery layer needed to make extensibility work for users, authors, vendors, and PostgreSQL hackers.

PGConf.Dev 2026 Opens Today in Vancouver

rh@vonng.com (Ruohang Feng) — Tue, 19 May 2026 00:00:00 +0000

PGConf.Dev 2026 opens in Vancouver as the PostgreSQL project marks its 30th anniversary. I will also be speaking on Extensions for Everyone.

The pgBackRest Rescue and Open Source's Forced Price Discovery

rh@vonng.com (Ruohang Feng) — Tue, 05 May 2026 00:00:00 +0000

Seven days after pgBackRest was archived, David Steele said a coalition of sponsors was nearly in place and the project would probably live on. This was not just a heartwarming community story. It was a remarkably clean exercise in forcing the market to price an open-source commons.

pgBackRest is No Longer Maintained

rh@vonng.com (Ruohang Feng) — Thu, 30 Apr 2026 00:00:00 +0000

Its maintainer, under pressure to make a living, has formally archived pgBackRest, the PostgreSQL ecosystem’s most important backup tool. The entire PostgreSQL community needs to think seriously about how critical open-source dependencies can be sustained.

Give DBA Agents a Body

rh@vonng.com (Ruohang Feng) — Sun, 26 Apr 2026 00:00:00 +0000

Today’s models are smart enough. What they lack is a body: a deterministic runtime that is observable, controllable, and reversible. Pigsty is evolving from a PostgreSQL distribution into an Agent Runtime, giving DBA and Dev Agents the operational reach and context they need to enter real production environments.

MySQL 9.7: Same Old Leftovers, Reheated

rh@vonng.com (Ruohang Feng) — Tue, 21 Apr 2026 00:00:00 +0000

MySQL 9.7 is the first LTS release in the 9.x line. Its vector support is still all show, its years-late optimizer is disabled by default, and three years of Innovation Releases have produced remarkably little.

The Three-Way Endgame: Why Agent Memory Frameworks Are a Dead End

rh@vonng.com (Ruohang Feng) — Sun, 19 Apr 2026 00:00:00 +0000

A cold shower for the red-hot agent memory market—not because agents do not need memory, but because memory is the endgame moat. That moat belongs to models, harnesses, and databases, not today’s “memory frameworks.”

504 Extensions: Expand the PostgreSQL Landscape

rh@vonng.com (Ruohang Feng) — Mon, 13 Apr 2026 00:00:00 +0000

One GitHub issue turned into an extension sprint. 32 new additions, 504 in total, say a lot about where PostgreSQL is headed.

Why PostgreSQL Won in the AI Era

rh@vonng.com (Ruohang Feng) — Sat, 11 Apr 2026 00:00:00 +0000

Boring technology won the wildest era. A look at extensibility, agent choice, database cloning, and the future of the DBA.

PostgreSQL vs. MySQL in 2026

rh@vonng.com (Ruohang Feng) — Fri, 03 Apr 2026 00:00:00 +0000

By 2026, PostgreSQL has won the market for new database adoption, outperforming MySQL across developer adoption, vendor strategy, capital markets, and community governance. MySQL still owns the installed base; Postgres owns the growth.

Digoal, the Face of PostgreSQL at Alibaba Cloud, Has Left

rh@vonng.com (Ruohang Feng) — Thu, 02 Apr 2026 00:00:00 +0000

Alibaba Cloud’s leading PostgreSQL advocate has walked away, exposing a deeper struggle over the direction of China’s cloud database market.

Put Your AI Agent's State in a Database

rh@vonng.com (Ruohang Feng) — Fri, 20 Mar 2026 00:00:00 +0000

Put an AI agent’s working directory, configuration, and memory on a PGFS mount, and you are effectively storing its state in PostgreSQL. That gives you not only a PITR “time machine,” but also a shared workspace and shared memory for multiple agents across multiple devices.

InsForge: A Supabase Built for Vibe Coding

rh@vonng.com (Ruohang Feng) — Wed, 11 Mar 2026 00:00:00 +0000

InsForge tries to package PostgreSQL, auth, storage, deployment, and an MCP-facing semantic layer into a backend stack designed for AI agents. It feels like a Supabase rebuilt for the vibe-coding era.

Is Oracle-Compatible Postgres Actually Useful?

rh@vonng.com (Ruohang Feng) — Sun, 22 Feb 2026 00:00:00 +0000

A migration case with only a JAR and no source code shows why Oracle syntax compatibility is not always a fake requirement, and how IvorySQL + Pigsty can absorb legacy debt at low cost.

Urgent Advisory: Pause PostgreSQL Minor-Release Installs and Upgrades

rh@vonng.com (Ruohang Feng) — Thu, 19 Feb 2026 00:00:00 +0000

The PostgreSQL 18.2 minor-release train introduced regressions in substring() and WAL replay. Hold off on fresh deployments and upgrades, then update promptly after the out-of-cycle releases ship on 2026-02-26.

The Agent Moat: Runtime

rh@vonng.com (Ruohang Feng) — Fri, 06 Feb 2026 00:00:00 +0000

A mediocre local who knows the terrain beats a genius parachuted into unknown territory. Intelligence without context is idle. An agent without a runtime is vapor.

The Great Software Meltdown: When Translation Layers Get Squashed

rh@vonng.com (Ruohang Feng) — Sat, 31 Jan 2026 00:00:00 +0000

SaaS and workflow software are dead. From APPs & GUIs to Agents, Databases, and CLI.

Agent OS: We're Building DOS Again

rh@vonng.com (Ruohang Feng) — Mon, 26 Jan 2026 00:00:00 +0000

LLM = CPU. Context = RAM. Database = Disk. Agent = App. The mapping is surprisingly clean. And if OS history is any guide, we may know what comes next — and what’s still missing.

How to Actually Do PostgreSQL High Availability

rh@vonng.com (Ruohang Feng) — Fri, 23 Jan 2026 00:00:00 +0000

A deep dive into the SOTA approach for PostgreSQL HA. RTO/RPO breakdown, from theory to production. If you’re still wrestling with PG HA, this might save you years.

Git for Data: Instant PostgreSQL Database Cloning

rh@vonng.com (Ruohang Feng) — Sat, 27 Dec 2025 00:00:00 +0000

How to instantly clone a massive PostgreSQL database without consuming extra storage? PostgreSQL 18 and XFS can spark some serious magic.

Data 2025: The year in review with Mike Stonebraker

rh@vonng.com (Ruohang Feng) — Wed, 24 Dec 2025 00:00:00 +0000

A conversation between Mike Stonebraker (MIT CSAIL, Turing Award Winner, Creator of PostgreSQL), Andy Pavlo (Carnegie Mellon University), and the DBOS team.

What Kind of Database Do AI Agents Need?

rh@vonng.com (Ruohang Feng) — Sun, 21 Dec 2025 00:00:00 +0000

The bottleneck for AI agents is not the database kernel, but integration above it. Muscle memory (in-database computation), associative memory (vector-graph fusion), and the courage to experiment (Git for Data) will be critical—none of them requires a new engine.

Why PostgreSQL Will Dominate the AI Era

rh@vonng.com (Ruohang Feng) — Mon, 01 Dec 2025 00:00:00 +0000

Context window economics, the polyglot persistence problem, and the triumph of zero-glue architecture make PostgreSQL the database king of the AI era.

Forging a China-Rooted, Global PostgreSQL Distro

rh@vonng.com (Ruohang Feng) — Thu, 27 Nov 2025 00:00:00 +0000

PostgreSQL already won. The real battle is the distro layer. Will Chinese developers watch from the sideline or craft a PG “Ubuntu” for the world?

Don't Run Docker Postgres for Production!

rh@vonng.com (Ruohang Feng) — Thu, 20 Nov 2025 00:00:00 +0000

Tons of users running the official docker postgres image got burned during recent minor version upgrades. A friendly reminder: think twice before containerizing production databases.

PG Extension Cloud: Unlocking PostgreSQL’s Entire Ecosystem

rh@vonng.com (Ruohang Feng) — Wed, 12 Nov 2025 00:00:00 +0000

Free, open, no VPN. Install PostgreSQL and 431 extensions on 14 Linux distros × 6 PG versions via native RPM/DEB—and a tiny CLI.

The PostgreSQL 'Supply Cut' and Trust Issues in Software Supply Chain

rh@vonng.com (Ruohang Feng) — Fri, 15 Aug 2025 00:00:00 +0000

PostgreSQL official repos cut off global mirror sync channels, open-source binaries supply disrupted, revealing the true colors of various database and cloud vendors.

Column: Postgres Mage

rh@vonng.com (Ruohang Feng) — Fri, 08 Aug 2025 00:00:00 +0000

Navigation of articles about PostgreSQL development, administration, principles, ecosystem, tools, architecture design, performance optimization, troubleshooting, and more.

PostgreSQL Dominates Database World, but Who Will Devour PG?

rh@vonng.com (Ruohang Feng) — Tue, 05 Aug 2025 00:00:00 +0000

The same forces that once led MongoDB and MySQL toward closure are now at work in the PostgreSQL ecosystem. The PG world needs a distribution that represents “software freedom” values.

PostgreSQL Has Dominated the Database World

rh@vonng.com (Ruohang Feng) — Thu, 31 Jul 2025 00:00:00 +0000

The 2025 SO global developer survey results are fresh out, and PostgreSQL has become the most popular, most loved, and most wanted database for the third consecutive year. Nothing can stop PostgreSQL from consolidating the entire database world!

Dongchedi Just Exposed “Smart Driving.” Where’s Our Dongku-Di?

rh@vonng.com (Ruohang Feng) — Sat, 26 Jul 2025 00:00:00 +0000

Imagine a “closed-course” shootout for domestic databases and clouds, the way Dongchedi just humiliated 30+ autonomous cars. This industry needs its own stress test.

Google AI Toolbox: Production-Ready Database MCP is Here?

rh@vonng.com (Ruohang Feng) — Wed, 09 Jul 2025 00:00:00 +0000

Google recently launched a database MCP toolbox, perhaps the first production-ready solution.

PGDG Cuts Off Mirror Sync Channel

rh@vonng.com (Ruohang Feng) — Mon, 07 Jul 2025 00:00:00 +0000

PGDG cuts off FTP rsync sync channels, global mirror sites universally disconnected - this time they really strangled global users’ supply chain.

Stop Arguing, The AI Era Database Has Been Settled

rh@vonng.com (Ruohang Feng) — Tue, 03 Jun 2025 00:00:00 +0000

The database for the AI era has been settled. Capital markets are making intensive moves on PostgreSQL targets, with PG having become the default database for the AI era.

Scaling Postgres to the next level at OpenAI

rh@vonng.com (Ruohang Feng) — Mon, 19 May 2025 00:00:00 +0000

At PGConf.Dev 2025, Bohan Zhang from OpenAI shared a session titled Scaling Postgres to the next level at OpenAI, giving us a peek into the database usage of a top-tier unicorn.

In the AI Era, Software Starts at the Database

rh@vonng.com (Ruohang Feng) — Sun, 27 Apr 2025 00:00:00 +0000

Future software = Agent + Database. No middle tiers, just agents issuing CRUD. Database skills age well, and PostgreSQL is poised to be the agent-era default.

MySQL vs. PostgreSQL @ 2025

rh@vonng.com (Ruohang Feng) — Thu, 17 Apr 2025 00:00:00 +0000

A 2025 reality check on where PostgreSQL stands relative to MySQL across features, performance, quality, and ecosystem.

Postgres Extension Day - See You There!

rh@vonng.com (Ruohang Feng) — Wed, 09 Apr 2025 00:00:00 +0000

The annual PostgreSQL developer conference will be held in Montreal in May. Like the first PG Con.Dev, there’s also an additional dedicated event - Postgres Extensions Day

OrioleDB is Coming! 4x Performance, Eliminates Pain Points, Storage-Compute Separation

rh@vonng.com (Ruohang Feng) — Sun, 06 Apr 2025 00:00:00 +0000

A PG kernel fork acquired by Supabase, claiming to solve PG’s XID wraparound problem, eliminate table bloat issues, improve performance by 4x, and support cloud-native storage. Now part of the Pigsty family.

OpenHalo: MySQL Wire-Compatible PostgreSQL is Here!

rh@vonng.com (Ruohang Feng) — Thu, 03 Apr 2025 00:00:00 +0000

What? PostgreSQL can now be accessed using MySQL clients? That’s right, openHalo, which was open-sourced on April Fool’s Day, provides exactly this capability and has now joined the Pigsty kernel family.

PGFS: Using Database as a Filesystem

rh@vonng.com (Ruohang Feng) — Fri, 21 Mar 2025 00:00:00 +0000

Leverage JuiceFS to turn PostgreSQL into a filesystem with PITR capabilities!

Database Planet Collision: When PG Falls for DuckDB

rh@vonng.com (Ruohang Feng) — Wed, 12 Mar 2025 00:00:00 +0000

If you ask me, we’re on the brink of a cosmic collision in database-land, and Postgres + DuckDB is the meteor we should all be watching.

Alicloud’s rds_duckdb: Tribute or Rip-Off?

rh@vonng.com (Ruohang Feng) — Thu, 06 Mar 2025 00:00:00 +0000

Does bolting DuckDB onto RDS suddenly make open-source Postgres ‘trash’? Business and open source should be symbiotic. If a vendor only extracts without giving back, the community will spit it out."

Comparing Oracle and PostgreSQL Transaction Systems

rh@vonng.com (Ruohang Feng) — Thu, 27 Feb 2025 00:00:00 +0000

The PG community has started punching up: Cybertec’s Laurenz Albe breaks down how Oracle’s transaction system stacks against PostgreSQL.

PostgreSQL Ecosystem Frontier Developments

rh@vonng.com (Ruohang Feng) — Fri, 24 Jan 2025 00:00:00 +0000

Sharing some interesting recent developments in the PG ecosystem.

Database as Business Architecture

rh@vonng.com (Ruohang Feng) — Wed, 22 Jan 2025 00:00:00 +0000

Databases are the core of business architecture, but what happens if we go further and let databases become the business architecture itself?

Pig, The Postgres Extension Wizard

rh@vonng.com (Ruohang Feng) — Sun, 29 Dec 2024 00:00:00 +0000

Why would we need yet another package manager for PostgreSQL & extensions?

7 Databases in 7 Weeks (2025)

rh@vonng.com (Ruohang Feng) — Tue, 03 Dec 2024 00:00:00 +0000

Is PostgreSQL the king of boring databases? Here are seven databases worth studying in 2025: PostgreSQL, SQLite, DuckDB, ClickHouse, FoundationDB, TigerBeetle, and CockroachDB—each deserving a week of deep exploration.

Solving the 24-Point Card Game with a Single SQL Query

rh@vonng.com (Ruohang Feng) — Tue, 03 Dec 2024 00:00:00 +0000

A fun but devious challenge: solve the 24-point card game in SQL. Here is the PostgreSQL answer.

Don't Upgrade! Released and Immediately Pulled - Even PostgreSQL Isn't Immune to Epic Fails

rh@vonng.com (Ruohang Feng) — Sat, 16 Nov 2024 00:00:00 +0000

Never deploy on Friday, or you’ll be working all weekend! PostgreSQL minor releases were pulled on the day of release, requiring emergency rollback.

PostgreSQL 12 End-of-Life, PG 17 Takes the Throne

rh@vonng.com (Ruohang Feng) — Thu, 14 Nov 2024 00:00:00 +0000

PG17 achieved extension ecosystem adaptation in half the time of PG16, with 300 available extensions ready for production use. PG 12 officially exits support lifecycle.

The Ideal Way to Deliver PostgreSQL Extensions

rh@vonng.com (Ruohang Feng) — Sat, 02 Nov 2024 00:00:00 +0000

PostgreSQL is eating the database world through extensibility. This post introduces the Pigsty extension repository, which packaged 390 PostgreSQL extensions at launch and keeps growing through the Pigsty extension catalog.

PostgreSQL 17 Released: No More Pretending!

rh@vonng.com (Ruohang Feng) — Thu, 26 Sep 2024 00:00:00 +0000

PostgreSQL is now the world’s most advanced open-source database and has become the preferred open-source database for organizations of all sizes, matching or exceeding top commercial databases.

MongoDB Has No Future: Good Marketing Can't Save a Rotten Mango

rh@vonng.com (Ruohang Feng) — Wed, 04 Sep 2024 00:00:00 +0000

MongoDB has a terrible track record on integrity, lackluster products and technology, gets beaten by PG in correctness, performance, and functionality, with collapsing developer reputation, declining popularity, stock price halving, and expanding losses. Provocative marketing against PG can’t save it with “good marketing.”

Can PostgreSQL Replace Microsoft SQL Server?

rh@vonng.com (Ruohang Feng) — Mon, 02 Sep 2024 00:00:00 +0000

PostgreSQL can directly replace Oracle, SQL Server, and MongoDB at the kernel level. Of course, the most thorough replacement is SQL Server - AWS’s Babelfish provides wire-protocol-level compatibility.

Whoever Integrates DuckDB Best Wins the OLAP World

rh@vonng.com (Ruohang Feng) — Tue, 13 Aug 2024 00:00:00 +0000

Just like the vector database extension race two years ago, the current PostgreSQL ecosystem extension competition has begun revolving around DuckDB. MotherDuck’s official entry into the PostgreSQL extension space undoubtedly signals that competition has entered white-hot territory.

StackOverflow 2024 Survey: PostgreSQL Has Gone Completely Berserk

rh@vonng.com (Ruohang Feng) — Thu, 25 Jul 2024 00:00:00 +0000

The 2024 StackOverflow Global Developer Survey results are fresh out, and PostgreSQL has become the most popular, most loved, and most wanted database globally for the second consecutive year. Nothing can stop PostgreSQL from devouring the entire database world anymore!

Self-Hosting Dify with PG, PGVector, and Pigsty

rh@vonng.com (Ruohang Feng) — Sat, 22 Jun 2024 00:00:00 +0000

Dify is an open-source LLM app development platform. This article explains how to self-host Dify using Pigsty.

PGCon.Dev 2024, The conf that shutdown PG for a week

rh@vonng.com (Ruohang Feng) — Mon, 17 Jun 2024 00:00:00 +0000

Experience & Feeling on the PGCon.Dev 2024

PostgreSQL 17 Beta1 Released!

rh@vonng.com (Ruohang Feng) — Fri, 24 May 2024 00:00:00 +0000

The PostgreSQL Global Development Group announces PostgreSQL 17’s first Beta version is now available. This time, PostgreSQL has truly burst the toothpaste tube!

Postgres is eating the database world

rh@vonng.com (Ruohang Feng) — Mon, 04 Mar 2024 00:00:00 +0000

PostgreSQL isn’t just a simple relational database; it’s a data management framework with the potential to engulf the entire database realm.

Technical Minimalism: Just Use PostgreSQL for Everything

rh@vonng.com (Ruohang Feng) — Mon, 19 Feb 2024 00:00:00 +0000

Whether production databases should be containerized remains a controversial topic. From a DBA’s perspective, I believe that currently, putting production databases in Docker is still a bad idea.

New PostgreSQL Ecosystem Player: ParadeDB

rh@vonng.com (Ruohang Feng) — Sun, 18 Feb 2024 00:00:00 +0000

ParadeDB aims to be an Elasticsearch alternative: “Modern Elasticsearch Alternative built on Postgres” — PostgreSQL for search and analytics.

PostgreSQL's Impressive Scalability

rh@vonng.com (Ruohang Feng) — Sat, 13 Jan 2024 00:00:00 +0000

This article describes how Cloudflare scaled to support 55 million requests per second using 15 PostgreSQL clusters, and PostgreSQL’s scalability performance.

PostgreSQL Wins 2024 Database of the Year Award! (Fifth Time)

rh@vonng.com (Ruohang Feng) — Fri, 05 Jan 2024 00:00:00 +0000

DB-Engines officially announced today that PostgreSQL has once again been crowned “Database of the Year.” This is the fifth time PG has received this honor in the past seven years. If not for Snowflake stealing the spotlight for two years, the database world would have almost become a PostgreSQL solo show.

PostgreSQL Convention 2024

rh@vonng.com (Ruohang Feng) — Mon, 27 Nov 2023 00:00:00 +0000

No rules, no standards. Some developer conventions for PostgreSQL 16.

PostgreSQL Macro Query Optimization with pg_stat_statements

rh@vonng.com (Ruohang Feng) — Thu, 26 Oct 2023 00:00:00 +0000

Query optimization is one of the core responsibilities of DBAs. This article introduces how to use metrics provided by pg_stat_statements for macro-level PostgreSQL query optimization.

FerretDB: PostgreSQL Disguised as MongoDB

rh@vonng.com (Ruohang Feng) — Sun, 08 Oct 2023 00:00:00 +0000

FerretDB aims to provide a truly open-source MongoDB alternative based on PostgreSQL.

How to Use pg_filedump for Data Recovery?

rh@vonng.com (Ruohang Feng) — Wed, 27 Sep 2023 00:00:00 +0000

Backups are a DBA’s lifeline — but what if your PostgreSQL database has already exploded and you have no backups? Maybe pg_filedump can help you!

PostgreSQL, The most successful database

rh@vonng.com (Ruohang Feng) — Wed, 28 Jun 2023 00:00:00 +0000

StackOverflow 2023 Survey shows PostgreSQL is the most popular, loved, and wanted database, solidifying its status as the ‘Linux of Database’.

AI Large Models and Vector Database PGVector

rh@vonng.com (Ruohang Feng) — Wed, 10 May 2023 00:00:00 +0000

This article focuses on vector databases hyped by AI, introduces the basic principles of AI embeddings and vector storage/retrieval, and demonstrates the functionality, performance, acquisition, and application of the vector database extension PGVECTOR through a concrete knowledge base retrieval case study.

How Powerful is PostgreSQL Really?

rh@vonng.com (Ruohang Feng) — Mon, 22 Aug 2022 00:00:00 +0000

Let performance data speak: Why PostgreSQL is the world’s most advanced open-source relational database, aka the world’s most successful database. MySQL vs PostgreSQL performance showdown and distributed database reality check.

Why PostgreSQL is the Most Successful Database?

rh@vonng.com (Ruohang Feng) — Tue, 12 Jul 2022 00:00:00 +0000

Database users are developers, but what about developers’ preferences, likes, and choices? Looking at StackOverflow survey results over the past six years, it’s clear that in 2022, PostgreSQL has won all three categories, becoming literally the “most successful database”

Ready-to-Use PostgreSQL Distribution: Pigsty

rh@vonng.com (Ruohang Feng) — Mon, 24 May 2021 00:00:00 +0000

Yesterday I gave a live presentation in the PostgreSQL Chinese community, introducing the open-source PostgreSQL full-stack solution — Pigsty

Why Does PostgreSQL Have a Bright Future?

rh@vonng.com (Ruohang Feng) — Sat, 08 May 2021 00:00:00 +0000

Databases are the core component of information systems, relational databases are the absolute backbone of databases, and PostgreSQL is the world’s most advanced open source relational database. With such favorable timing and positioning, how can it not achieve great success?

Implementing Advanced Fuzzy Search

rh@vonng.com (Ruohang Feng) — Fri, 05 Mar 2021 00:00:00 +0000

How to implement relatively complex fuzzy search logic in PostgreSQL?

Localization and Collation Rules in PostgreSQL

rh@vonng.com (Ruohang Feng) — Fri, 05 Mar 2021 00:00:00 +0000

What? Don’t know what COLLATION is? Remember one thing: using C COLLATE is always the right choice!

PostgreSQL Logical Replication Deep Dive

rh@vonng.com (Ruohang Feng) — Wed, 03 Mar 2021 00:00:00 +0000

This article introduces the principles and best practices of logical replication in PostgreSQL 13.

A Methodology for Diagnosing PostgreSQL Slow Queries

rh@vonng.com (Ruohang Feng) — Tue, 23 Feb 2021 00:00:00 +0000

Slow queries are the sworn enemy of OLTP databases. Here’s how to identify, analyze, and fix them using metrics (Pigsty dashboards), pg_stat_statements, and logs.

Incident-Report: Patroni Failure Due to Time Travel

rh@vonng.com (Ruohang Feng) — Mon, 22 Feb 2021 00:00:00 +0000

Machine restarted due to failure, NTP service corrected PG time after PG startup, causing Patroni to fail to start.

Online Primary Key Column Type Change

rh@vonng.com (Ruohang Feng) — Fri, 15 Jan 2021 00:00:00 +0000

How to change column types online, such as upgrading from INT to BIGINT?

Golden Monitoring Metrics: Errors, Latency, Throughput, Saturation

rh@vonng.com (Ruohang Feng) — Fri, 06 Nov 2020 00:00:00 +0000

Understanding the golden monitoring metrics in PostgreSQL

Database Cluster Management Concepts and Entity Naming Conventions

rh@vonng.com (Ruohang Feng) — Wed, 03 Jun 2020 00:00:00 +0000

Concepts and their naming are very important. Naming style reflects an engineer’s understanding of system architecture. Poorly defined concepts lead to communication confusion, while carelessly set names create unexpected additional burden. Therefore, they need careful design.

PostgreSQL's KPI

rh@vonng.com (Ruohang Feng) — Fri, 29 May 2020 00:00:00 +0000

Managing databases is similar to managing people - both need KPIs (Key Performance Indicators). So what are database KPIs? This article introduces a way to measure PostgreSQL load: using a single horizontally comparable metric that is basically independent of workload type and machine type, called PG Load.

Online PostgreSQL Column Type Migration

rh@vonng.com (Ruohang Feng) — Thu, 30 Jan 2020 00:00:00 +0000

How to modify PostgreSQL column types online? A general approach

Frontend-Backend Communication Wire Protocol

rh@vonng.com (Ruohang Feng) — Tue, 12 Nov 2019 00:00:00 +0000

Understanding the TCP protocol used for communication between PostgreSQL server and client, and printing messages using Go

Transaction Isolation Level Considerations

rh@vonng.com (Ruohang Feng) — Tue, 12 Nov 2019 00:00:00 +0000

PostgreSQL actually has only two transaction isolation levels: Read Committed and Serializable

Incident: PostgreSQL Extension Installation Causes Connection Failure

rh@vonng.com (Ruohang Feng) — Thu, 13 Jun 2019 00:00:00 +0000

Today encountered an interesting case where a customer reported database connection issues caused by extensions.

CDC Change Data Capture Mechanisms

rh@vonng.com (Ruohang Feng) — Wed, 12 Jun 2019 00:00:00 +0000

Change Data Capture is an interesting ETL alternative solution.

Locks in PostgreSQL

rh@vonng.com (Ruohang Feng) — Tue, 11 Jun 2019 00:00:00 +0000

Snapshot isolation does most of the heavy lifting in PG, but locks still matter. Here’s a practical guide to table locks, row locks, intention locks, and pg_locks.

O(n2) Complexity of GIN Search

rh@vonng.com (Ruohang Feng) — Fri, 12 Apr 2019 00:00:00 +0000

When GIN indexes are used to search with very long keyword lists, performance degrades significantly. This article explains why GIN index keyword search has O(n^2) time complexity.

PostgreSQL Common Replication Topology Plans

rh@vonng.com (Ruohang Feng) — Fri, 29 Mar 2019 00:00:00 +0000

Replication is one of the core issues in system architecture.

Warm Standby: Using pg_receivewal

rh@vonng.com (Ruohang Feng) — Sat, 02 Mar 2019 00:00:00 +0000

There are various backup strategies. Physical backups can usually be divided into four types.

Incident-Report: Connection-Pool Contamination Caused by pg_dump

rh@vonng.com (Ruohang Feng) — Tue, 11 Dec 2018 00:00:00 +0000

Sometimes, interactions between components manifest in subtle ways. For example, using pg_dump to export data from a connection pool can cause connection pool contamination issues.

PostgreSQL Data Page Corruption Repair

rh@vonng.com (Ruohang Feng) — Thu, 29 Nov 2018 00:00:00 +0000

Using binary editing to repair PostgreSQL data pages, and how to make a primary key query return two records.

Relation Bloat Monitoring and Management

rh@vonng.com (Ruohang Feng) — Sat, 06 Oct 2018 00:00:00 +0000

PostgreSQL uses MVCC as its primary concurrency control technology. While it has many benefits, it also brings other effects, such as relation bloat.

Getting Started with PipelineDB

rh@vonng.com (Ruohang Feng) — Fri, 07 Sep 2018 00:00:00 +0000

PipelineDB is a PostgreSQL extension for streaming analytics. Here’s how to install it and build continuous views over live data.

TimescaleDB Quick Start

rh@vonng.com (Ruohang Feng) — Fri, 07 Sep 2018 00:00:00 +0000

TimescaleDB is a PostgreSQL extension plugin that provides time-series database functionality.

Incident-Report: Integer Overflow from Rapid Sequence Number Consumption

rh@vonng.com (Ruohang Feng) — Fri, 20 Jul 2018 00:00:00 +0000

If you use Integer sequences on tables, you should consider potential overflow scenarios.

Incident-Report: PostgreSQL Transaction ID Wraparound

rh@vonng.com (Ruohang Feng) — Fri, 20 Jul 2018 00:00:00 +0000

XID WrapAround is perhaps a unique type of failure specific to PostgreSQL

GeoIP Geographic Reverse Lookup Optimization

rh@vonng.com (Ruohang Feng) — Sat, 07 Jul 2018 00:00:00 +0000

A common requirement in application development is GeoIP conversion - converting source IP addresses to geographic coordinates or administrative divisions (country-state-city-county-town-village)

PostgreSQL Trigger Usage Considerations

rh@vonng.com (Ruohang Feng) — Sat, 07 Jul 2018 00:00:00 +0000

Detailed understanding of trigger management and usage in PostgreSQL

PostgreSQL Development Convention (2018 Edition)

rh@vonng.com (Ruohang Feng) — Wed, 20 Jun 2018 00:00:00 +0000

Without rules, there can be no order. This article compiles a development specification for PostgreSQL database principles and features, which can reduce confusion encountered when using PostgreSQL.

What Are PostgreSQL's Advantages?

rh@vonng.com (Ruohang Feng) — Sun, 10 Jun 2018 00:00:00 +0000

PostgreSQL’s slogan is “The World’s Most Advanced Open-Source Relational Database,” but I think the most vivid characterization should be: The Full-Stack Database That Does It All - one tool to rule them all.

Efficient Administrative Region Lookup with PostGIS

rh@vonng.com (Ruohang Feng) — Wed, 06 Jun 2018 00:00:00 +0000

How to efficiently solve the typical reverse geocoding problem: determining administrative regions based on user coordinates.

KNN Ultimate Optimization: From RDS to PostGIS

rh@vonng.com (Ruohang Feng) — Wed, 06 Jun 2018 00:00:00 +0000

Ultimate optimization of KNN problems, from traditional relational design to PostGIS

Monitoring Table Size in PostgreSQL

rh@vonng.com (Ruohang Feng) — Mon, 14 May 2018 00:00:00 +0000

Tables in PostgreSQL correspond to many physical files. This article explains how to calculate the actual size of a table in PostgreSQL.

PgAdmin Installation and Configuration

rh@vonng.com (Ruohang Feng) — Sat, 14 Apr 2018 00:00:00 +0000

PgAdmin is a GUI program for managing PostgreSQL, written in Python, but it’s quite dated and requires some additional configuration.

Incident-Report: Uneven Load Avalanche

rh@vonng.com (Ruohang Feng) — Sun, 08 Apr 2018 00:00:00 +0000

Recently there was a perplexing incident where a database had half its data volume and load migrated away, but ended up being overwhelmed due to increased load.

Distinct On: Remove Duplicate Data

rh@vonng.com (Ruohang Feng) — Fri, 06 Apr 2018 00:00:00 +0000

Use Distinct On extension clause to quickly find records with maximum/minimum values within groups

Function Volatility Classification Levels

rh@vonng.com (Ruohang Feng) — Fri, 06 Apr 2018 00:00:00 +0000

PostgreSQL functions have three volatility levels by default. Proper use can significantly improve performance.

Implementing Mutual Exclusion Constraints with Exclude

rh@vonng.com (Ruohang Feng) — Fri, 06 Apr 2018 00:00:00 +0000

Exclude constraint is a PostgreSQL extension that can implement more advanced and sophisticated database constraints.

PostgreSQL Routine Maintenance

rh@vonng.com (Ruohang Feng) — Sat, 10 Feb 2018 00:00:00 +0000

Cars need oil changes, databases need maintenance. For PG, three important maintenance tasks: backup, repack, vacuum

Backup and Recovery Methods Overview

rh@vonng.com (Ruohang Feng) — Fri, 09 Feb 2018 00:00:00 +0000

Backup is the foundation of a DBA’s livelihood. With backups, there’s no need to panic.

PgBackRest2 Documentation

rh@vonng.com (Ruohang Feng) — Wed, 07 Feb 2018 00:00:00 +0000

PgBackRest is a set of PostgreSQL backup tools written in Perl

Pgbouncer Quick Start

rh@vonng.com (Ruohang Feng) — Wed, 07 Feb 2018 00:00:00 +0000

Pgbouncer is a lightweight database connection pool. This guide covers basic Pgbouncer configuration, management, and usage.

PostgreSQL Server Log Regular Configuration

rh@vonng.com (Ruohang Feng) — Tue, 06 Feb 2018 00:00:00 +0000

It’s recommended to configure PostgreSQL’s log format as CSV for easy analysis, and it can be directly imported into PostgreSQL data tables.

Testing Disk Performance with FIO

rh@vonng.com (Ruohang Feng) — Tue, 06 Feb 2018 00:00:00 +0000

FIO is a convenient tool for testing disk I/O performance

Using sysbench to Test PostgreSQL Performance

rh@vonng.com (Ruohang Feng) — Tue, 06 Feb 2018 00:00:00 +0000

Although PostgreSQL provides pgbench, sometimes you need sysbench to outperform MySQL.

Changing Engines Mid-Flight — PostgreSQL Zero-Downtime Data Migration

rh@vonng.com (Ruohang Feng) — Tue, 06 Feb 2018 00:00:00 +0000

Data migration typically involves stopping services for updates. Zero-downtime data migration is a relatively advanced operation.

Finding Unused Indexes

rh@vonng.com (Ruohang Feng) — Sun, 04 Feb 2018 00:00:00 +0000

Indexes are useful, but they’re not free. Unused indexes are a waste. Use these methods to identify unused indexes.

Batch Configure SSH Passwordless Login

rh@vonng.com (Ruohang Feng) — Sun, 07 Jan 2018 00:00:00 +0000

Quick configuration for passwordless login to all machines

Wireshark Packet Capture Protocol Analysis

rh@vonng.com (Ruohang Feng) — Fri, 05 Jan 2018 00:00:00 +0000

Wireshark is a very useful tool, especially suitable for analyzing network protocols. Here’s a simple introduction to using Wireshark for packet capture and PostgreSQL protocol analysis.

The Versatile file_fdw — Reading System Information from Your Database

rh@vonng.com (Ruohang Feng) — Fri, 01 Dec 2017 00:00:00 +0000

With file_fdw, you can easily view operating system information, fetch network data, and feed various data sources into your database for unified viewing and management.

Common Linux Statistics CLI Tools

rh@vonng.com (Ruohang Feng) — Thu, 07 Sep 2017 00:00:00 +0000

top, free, vmstat, iostat: Quick reference for four commonly used CLI tools

Installing PostGIS from Source

rh@vonng.com (Ruohang Feng) — Thu, 07 Sep 2017 00:00:00 +0000

PostGIS is PostgreSQL’s killer extension, but compiling and installing it isn’t easy.

Go Database Tutorial: database/sql

rh@vonng.com (Ruohang Feng) — Thu, 24 Aug 2017 00:00:00 +0000

Similar to JDBC, Go also has a standard database access interface. This article details how to use database/sql in Go and important considerations.

Implementing Cache Synchronization with Go and PostgreSQL

rh@vonng.com (Ruohang Feng) — Thu, 03 Aug 2017 00:00:00 +0000

Cleverly utilizing PostgreSQL’s Notify feature, you can conveniently notify applications of metadata changes and implement trigger-based logical replication.

Auditing Data Changes with Triggers

rh@vonng.com (Ruohang Feng) — Fri, 09 Jun 2017 00:00:00 +0000

Sometimes we want to record important metadata changes for audit purposes. PostgreSQL triggers can conveniently solve this need automatically.

Building an ItemCF Recommender in Pure SQL

rh@vonng.com (Ruohang Feng) — Wed, 05 Apr 2017 00:00:00 +0000

Five minutes, PostgreSQL, and the MovieLens dataset—that’s all you need to implement a classic item-based collaborative filtering recommender.

UUID Properties, Principles and Applications

rh@vonng.com (Ruohang Feng) — Sun, 06 Nov 2016 00:00:00 +0000

UUID properties, principles and applications, and how to manipulate UUIDs using PostgreSQL stored procedures.

PostgreSQL MongoFDW Installation and Deployment

rh@vonng.com (Ruohang Feng) — Sat, 28 May 2016 00:00:00 +0000

Recently had business requirements to access MongoDB through PostgreSQL FDW, but compiling MongoDB FDW is really a nightmare.