PG-Admin on Vonng

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.

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.

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.

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!

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

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.

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

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.

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.

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.