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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.
19 hrs ago
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Haider Z
[FREE] Why Query Performance Degrades and Causes High CPU
Stale Statistics, Reset Stats, and Missing ANALYZE: The Hidden Causes Behind Query Plan Regressions
Feb 13
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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.
Feb 11
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Haider Z
1
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How to Find & Fix PostgreSQL Table Bloat with 13 SQL Queries [Full RCA]
Nov 26, 2025
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Haider Z
7
[Premium] PostgreSQL Error That Means It's Already Too Late: invalid page in block
Feb 4
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Haider Z
4
[Premium] PostgreSQL OOM Crash: 11 Diagnostic Queries
Jan 16
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Haider Z
3
How Apollo Hospitals Migrated 25 Years of Oracle to PostgreSQL
Jan 5
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Haider Z
4
1
PostgreSQL Sev-1 Survival Guide: 15+ Emergency SQL Queries
Nov 28, 2025
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Haider Z
3
PostgreSQL at 100% CPU with Normal Query Load: The $2M Lesson in Stale
Nov 6, 2025
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Haider Z
6
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[RCA] PostgreSQL Limit Nobody Monitors: How MultiXact Member Exhaustion Caused Four Outages in One Week
Metronome's dashboards showed 50% utilization. PostgreSQL still refused all writes. The blind spot: MultiXact member space vs ID count
Feb 9
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Haider Z
2
[FREE] Why Linux Kills PostgreSQL: What the Manual Says (And How to Fix It)
The official documentation explains exactly how to prevent Linux from killing your database. Here's what it says.
Feb 6
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Haider Z
2
[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.
Feb 4
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Haider Z
4
[DBEng] Azure HorizonDB Architecture Details Revealed from Microsoft
A database engineering breakdown of Microsoft's next-generation PostgreSQL service.
Feb 2
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Haider Z
4
1
[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
Jan 30
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Haider Z
2
How Partition Key UPDATE Cause Serialization Failures
Why PostgreSQL triggers SQLSTATE 40001 during row movement and the architectural patterns to prevent it.
Jan 28
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Haider Z
1
[FREE] Missing Index: How to Find & Fix Performance Bottlenecks in PostgreSQL
Learn how to detect and fix PostgreSQL missing indexes. Improve slow query performance with safe index tuning, system views like pg_stat_user_tables…
Jan 26
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Haider Z
How Notion Sharded PostgreSQL Without Downtime
From 1 RDS to 96 Databases: A Masterclass in Horizontal Scaling and Sharding
Jan 21
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Haider Z
6
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[Premium] PostgreSQL High CPU Investigation: The Complete DBA Playbook 11+ Queries
How to Diagnose, Fix, and Prevent CPU Spikes from Crippling Your Database
Jan 19
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Haider Z
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The Sev-1 Database
I manage PostgreSQL, MySQL and MariaDB at Microsoft. Each week, I share practical takeaways from real incidents no theory, just what actually breaks and how to fix it.
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