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Notes for the problems that show up after launch: bad plans, awkward migrations, index debt, vacuum pressure, replica lag, and the small decisions that make PostgreSQL easier to operate.

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pgvector and RAG Indexes Slow Queries Locks and Transactions Backups and Durability Replication and WAL Connections and Pooling CPU, Memory, and I/O Vacuum and Bloat Cloud Providers

February 24, 20266 min read

Postgres Failover Readiness: The Drill That Tells You If You Are Lying to Yourself

Failover is mostly fine when you do not need it and broken when you do. Here is how to know which you have.

February 23, 20265 min read

When Replication Slots Eat the Disk: A Diagnostic Walkthrough

If your Postgres disk is growing and you cannot identify the culprit, replication slots are usually the answer. Here is the diagnostic sequence.

February 22, 20266 min read

Postgres Roles and Least Privilege: The Setup That Survives Audits

Most production databases run application traffic as a superuser. This is convenient and wrong. Here is the role hierarchy that takes a few hours to set up and saves you in the worst case.

February 21, 202612 min read

PostgreSQL Replication Monitoring: Lag, Slots, and Failover

Replication monitoring is not one lag number. You need to know stale-read risk, slot retention, replay delay, WAL growth, and whether failover would help or hurt.

February 20, 20267 min read

Row-Level Security in Postgres: Strong Defense, Costs You Will Encounter

RLS pushes access control into the database. It is more secure than application-side filters and slightly slower than no filter at all. Here is the framework for using it well.

February 19, 20266 min read

Postgres SSL Connections: Doing It Properly Without Losing a Day

SSL on Postgres is a one-line config change to enable and a multi-day project to do correctly. The default settings are not good enough.

February 18, 20266 min read

Auditing Sensitive Access in Postgres: Patterns That Survive Real Audits

"Did anyone read the customer table outside expected hours" is a common audit question. The answer is harder to produce than it should be unless you set up auditing deliberately.

February 17, 20266 min read

Connection Strings, Passwords, and Secrets: How to Stop Leaking Postgres Credentials

Most Postgres connection strings live in places they should not. Environment variables, config files, scripts, screenshots in Slack. Here is the discipline.

February 16, 20267 min read

AWS RDS Parameter Groups: The Postgres Settings That Actually Matter

RDS exposes hundreds of Postgres parameters through Parameter Groups. About a dozen of them are worth tuning. Here are the ones I always change and why.

February 15, 20266 min read

AWS Aurora Postgres Replica Lag: Different from Vanilla, Different to Diagnose

Aurora's replica lag has different mechanics than vanilla streaming replication. The dashboard metric "replica lag" can be misleading. Here is what it actually measures.

February 14, 202613 min read

PostgreSQL Locks and Deadlocks: Detection, Prevention, and Triage

Lock incidents feel mysterious because the database looks idle while requests wait. The fix starts with blockers, waiters, transaction age, and code paths that take locks in different orders.

February 13, 20265 min read

Google Cloud SQL Maintenance Windows: What Actually Happens and What to Plan For

Cloud SQL maintenance windows are mostly fine and occasionally not. Here is what happens during them, what gets restarted, and how to make sure your application survives.