The Sev-1 Database

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[Premium] The systemd Setting That Silently Breaks PostgreSQL Parallel Queries
The official documentation explains exactly why you're seeing "could not remove shared memory segment" warnings. Here's what it says and how to fix it.
 • Haider Z
[Premium] PostgreSQL Memory Architecture: Why work_mem Multiplies and Causes OOM
The official documentation tells you exactly why your database runs out of memory.
 • Haider Z
[Premium] PostgreSQL Error That Means It's Already Too Late: invalid page in block
Your queries aren't failing. Your database isn't throwing errors. But your data is already wrong.
 • Haider Z
[Premium] Don't Ignore This Warning Before PostgreSQL Shuts Down Your Database
When PostgreSQL warns "must be vacuumed within X transactions," you have exactly one chance to avoid a Sev-1
 • Haider Z
[Premium] PostgreSQL High CPU Investigation: The Complete DBA Playbook 11+ Queries
How to Diagnose, Fix, and Prevent CPU Spikes from Crippling Your Database
 • Haider Z
[Premium] PostgreSQL OOM Crash: 11 Diagnostic Queries
How to Diagnose, Fix, and Prevent Linux OOM Killer from Terminating Your Database
 • Haider Z
[Premium] PostgreSQL Disaster: How Unlogged Tables Wiped Out Customer Data + 8 Queries to Prevent It
A PostgreSQL post-mortem that cost $ in lost revenue and 3 months of customer data and how to check if you’re at risk right now
 • Haider Z
Your PostgreSQL Indexes Are Lying to You: 5 Queries to Expose the Truth
Stop guessing with your database performance. Learn how to identify unused, inefficient, and missing indexes in PostgreSQL using SQL to prevent downtime…
 • Haider Z
PostgreSQL Sev-1 Survival Guide: 15+ Emergency SQL Queries
Production down? Use this guide. Copy-paste SQL queries for lock contention, bloat, and wait events. Resolve PostgreSQL Sev-1 incidents fast.
 • Haider Z
How to Find & Fix PostgreSQL Table Bloat with 13 SQL Queries [Full RCA]
A practical guide to Postgres performance tuning, detecting dead tuples, solving sudden latency spikes, and repairing autovacuum failures using real…
 • Haider Z
Full RCA Deep Dive: How a Missing Connection Pooler Triggered a $10,000/Minute Downtime in Production
Why your App is one retry loop away from Disaster and how pooling saves you
 • Haider Z
Full RCA Deep Dive: PostgreSQL Security Upgrade Outage
FATAL: unsupported authentication method: 10 Why Client Drivers Killed the Zero-Downtime Upgrade
 • Haider Z
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