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PostgreSQL & MySQL guides from production experience

31 Articles
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All AWS RDS Database Performance High Availability MySQL Mysql Upgrade PostgreSQL PostgreSQL Query Tuning Tools Troubleshooting

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ProxySQL in Front of AWS RDS & Aurora MySQL — Part 2: Wiring ProxySQL to Aurora MySQL
MySQL AWS RDS High Availability Mon May 11 2026

ProxySQL in Front of AWS RDS & Aurora MySQL — Part 2: Wiring ProxySQL to Aurora MySQL

2 errors in 1,485 queries across a live Aurora failover — a 0.1s window vs. Part 1's 60s baseline. Here's the exact ProxySQL config that produced it.

ProxySQL in Front of AWS RDS & Aurora MySQL — Part 3: Query Routing, Read/Write Split, and Multiplexing
MySQL AWS RDS High Availability Mon May 11 2026

ProxySQL in Front of AWS RDS & Aurora MySQL — Part 3: Query Routing, Read/Write Split, and Multiplexing

How ProxySQL's query rules route by pattern, user, schema, and digest — and why SET @user_var, not HikariCP's defaults, is what actually breaks multiplexing.

ProxySQL in Front of AWS RDS & Aurora MySQL — Part 4: HA, Failover Patterns, and TLS
MySQL AWS RDS High Availability Mon May 11 2026

ProxySQL in Front of AWS RDS & Aurora MySQL — Part 4: HA, Failover Patterns, and TLS

Aurora topology flip: 15s. RDS Multi-AZ failover: 64s. Dual-node ProxySQL cluster sync timings, NLB detection gaps, backend TLS — all measured live on AWS.

ProxySQL in Front of AWS RDS & Aurora MySQL — Part 5: Monitoring, Tuning, and Troubleshooting
MySQL AWS RDS High Availability Mon May 11 2026

ProxySQL in Front of AWS RDS & Aurora MySQL — Part 5: Monitoring, Tuning, and Troubleshooting

ProxySQL + Aurora stack in production: query digest baselines, lag threshold sizing, zero-error rolling upgrade, and monitor-user revocation failure pattern.

PostgreSQL Failover Testing: Real Scenarios (Part 4)
PostgreSQL High Availability Thu Apr 23 2026

PostgreSQL Failover Testing: Real Scenarios (Part 4)

Test automatic and manual PostgreSQL failover. Kill the primary, watch Orchestrator promote, verify ProxySQL reroutes. Real outputs.

Orchestrator PostgreSQL Failover Configuration (Part 3)
PostgreSQL High Availability Thu Apr 23 2026

Orchestrator PostgreSQL Failover Configuration (Part 3)

Install Orchestrator 4.30.2 for PostgreSQL. Configure topology discovery, automatic and manual failover with pg_promote().

Cross-Account Database Monitoring with PMM and AWS Transit Gateway — Part 5: Backup, Recovery, and Node Reconfiguration
MySQL AWS RDS Thu Apr 23 2026

Cross-Account Database Monitoring with PMM and AWS Transit Gateway — Part 5: Backup, Recovery, and Node Reconfiguration

Configure weekly AWS Backup for the PMM EC2 instance, walk through the full recovery procedure after a failure, and reconfigure PMM client agents on x86_64 and aarch64 nodes after a PMM server IP change.

Cross-Account Database Monitoring with PMM and AWS Transit Gateway — Part 4: Alerting with PagerDuty and CloudWatch
MySQL AWS RDS Thu Apr 23 2026

Cross-Account Database Monitoring with PMM and AWS Transit Gateway — Part 4: Alerting with PagerDuty and CloudWatch

Configure PMM alerting end-to-end: custom MetricsQL alert templates, PagerDuty contact points, notification policies, CloudWatch data sources via IAM role assumption, and amtool for silence management.

ProxySQL PostgreSQL Read/Write Splitting Setup (Part 2)
PostgreSQL High Availability Thu Apr 23 2026

ProxySQL PostgreSQL Read/Write Splitting Setup (Part 2)

Configure ProxySQL 3.0.6 for PostgreSQL read/write splitting, health monitoring, and query routing. Tested on live VMs.

Cross-Account Database Monitoring with PMM and AWS Transit Gateway — Part 3: Installing PMM Server and Registering Services
MySQL AWS RDS Thu Apr 23 2026

Cross-Account Database Monitoring with PMM and AWS Transit Gateway — Part 3: Installing PMM Server and Registering Services

Install PMM Server on Docker, deploy PMM clients on x86_64 and aarch64 nodes, create monitoring users, and register MySQL, ProxySQL, and MariaDB RDS services at scale.

Cross-Account Database Monitoring with PMM and AWS Transit Gateway — Part 2: IAM Roles and Users
MySQL AWS RDS Thu Apr 23 2026

Cross-Account Database Monitoring with PMM and AWS Transit Gateway — Part 2: IAM Roles and Users

Configure cross-account IAM roles for PMM CloudWatch access and IAM users for Aurora OS metrics. Includes full trust policy, permissions policy, and Terraform references.

PostgreSQL HA Setup: Streaming Replication Guide (Part 1)
PostgreSQL High Availability Thu Apr 23 2026

PostgreSQL HA Setup: Streaming Replication Guide (Part 1)

Build a 3-node PostgreSQL 17 streaming replication cluster on Multipass VMs. Step 1 of a ProxySQL + Orchestrator HA series.

Cross-Account Database Monitoring with PMM and AWS Transit Gateway — Part 1: Architecture and TGW Setup
MySQL AWS RDS Thu Apr 23 2026

Cross-Account Database Monitoring with PMM and AWS Transit Gateway — Part 1: Architecture and TGW Setup

Set up centralized RDS monitoring across multiple AWS accounts using Percona Monitoring and Management (PMM) and AWS Transit Gateway. Full network, routing, and security group walkthrough.

How a MySQL UPDATE Actually Works: InnoDB Internals Animated
MySQL Database Performance Sun Apr 12 2026

How a MySQL UPDATE Actually Works: InnoDB Internals Animated

Step-by-step animation of what happens inside MySQL when you run an UPDATE. From client packet to redo log fsync — every layer of InnoDB explained with interactive visualization.

MySQL EXPLAIN Output Explained: The Complete Guide (2026)
MySQL Database Performance Sat Apr 11 2026

MySQL EXPLAIN Output Explained: The Complete Guide (2026)

Every column of MySQL EXPLAIN output decoded with real examples from a 680K-row production database. Learn what each access type means, when to worry, and how to fix the slow ones.

We Built a Free MySQL EXPLAIN Analyzer — Here's What It Catches That You're Missing
MySQL Tools Thu Apr 09 2026

We Built a Free MySQL EXPLAIN Analyzer — Here's What It Catches That You're Missing

Free MySQL & MariaDB EXPLAIN ANALYZE visualizer with 49 detection rules, smart index recommendations, and impact simulation. Tested against AI analysis on 50 unseen queries. 100% client-side.

MariaDB 10.6 to MySQL Aurora 8.0 Migration Guide — Part 5: Execution, Validation, Cutover, and Cleanup
MySQL AWS RDS Wed Apr 08 2026

MariaDB 10.6 to MySQL Aurora 8.0 Migration Guide — Part 5: Execution, Validation, Cutover, and Cleanup

Run the AWS DMS migration task, enable data validation, perform the cutover from MariaDB to Aurora MySQL, recreate indexes, and clean up all temporary AWS resources.

MariaDB 10.6 to MySQL Aurora 8.0 Migration Guide — Part 4: DMS Endpoints, Task Configuration, and Assessments
MySQL AWS RDS Wed Apr 08 2026

MariaDB 10.6 to MySQL Aurora 8.0 Migration Guide — Part 4: DMS Endpoints, Task Configuration, and Assessments

Configure AWS DMS source and target endpoints, set up DMS users, create the migration task with correct LOB and table mapping settings, and run pre-migration assessments.

MariaDB 10.6 to MySQL Aurora 8.0 Migration Guide — Part 3: Schema and User Migration
MySQL AWS RDS Wed Apr 08 2026

MariaDB 10.6 to MySQL Aurora 8.0 Migration Guide — Part 3: Schema and User Migration

Migrate schema and users from MariaDB 10.6 to Aurora MySQL 8.0. Covers mysqldump compatibility pipeline, incompatible object cleanup, index strategy for DMS, and user export with pt-show-grants.

MariaDB 10.6 to MySQL Aurora 8.0 Migration Guide — Part 2: AWS DMS Infrastructure Setup
MySQL AWS RDS Wed Apr 08 2026

MariaDB 10.6 to MySQL Aurora 8.0 Migration Guide — Part 2: AWS DMS Infrastructure Setup

Set up AWS DMS for MariaDB to Aurora MySQL migration. Step-by-step guide to IAM roles, replication instance sizing, VPC configuration, and security group rules.

MariaDB 10.6 to MySQL Aurora 8.0 Migration Guide — Part 1: Pre-Migration Requirements
MySQL AWS RDS Wed Apr 08 2026

MariaDB 10.6 to MySQL Aurora 8.0 Migration Guide — Part 1: Pre-Migration Requirements

Pre-migration checklist for migrating from MariaDB 10.6 to Amazon Aurora MySQL 8.0 via AWS DMS. Covers timeout settings, binlog configuration, and target validation.

MySQL 8.0 to 8.4 LTS Upgrade Guide — Part 5: Change Management, Troubleshooting, and Complete Checklist
MySQL Mysql Upgrade Mon Apr 06 2026

MySQL 8.0 to 8.4 LTS Upgrade Guide — Part 5: Change Management, Troubleshooting, and Complete Checklist

Complete MySQL 8.4 upgrade checklist with 41 items, 8 common troubleshooting scenarios, project timeline estimates, and change management templates for production upgrades.

MySQL 8.0 to 8.4 LTS Upgrade Guide — Part 4: Rollback Strategy and Post-Upgrade Validation
MySQL Mysql Upgrade Mon Apr 06 2026

MySQL 8.0 to 8.4 LTS Upgrade Guide — Part 4: Rollback Strategy and Post-Upgrade Validation

Plan your MySQL 8.4 rollback strategy before you start. Plus the complete post-upgrade validation checklist — version checks, replication health, optimizer stats, and monitoring.

MySQL 8.0 to 8.4 LTS Upgrade Guide — Part 3: Upgrade Execution
MySQL Mysql Upgrade Mon Apr 06 2026

MySQL 8.0 to 8.4 LTS Upgrade Guide — Part 3: Upgrade Execution

Three MySQL upgrade approaches compared — replication-based, in-place, and rolling replica. Step-by-step commands, configuration templates, and time estimates for each method.

MySQL 8.0 to 8.4 LTS Upgrade Guide — Part 2: Upgrade Testing
MySQL Mysql Upgrade Mon Apr 06 2026

MySQL 8.0 to 8.4 LTS Upgrade Guide — Part 2: Upgrade Testing

Learn how to test your MySQL 8.0 to 8.4 upgrade using pt-upgrade, dry-run procedures, application compatibility checks, and canary testing before touching production.

MySQL 8.0 to 8.4 LTS Upgrade Guide — Part 1: Pre-Upgrade Preparation
MySQL Mysql Upgrade Mon Apr 06 2026

MySQL 8.0 to 8.4 LTS Upgrade Guide — Part 1: Pre-Upgrade Preparation

MySQL 8.0 reached EOL on April 6, 2026. This guide covers every pre-upgrade step — backups, upgrade checker, removed parameters, authentication migration, and schema fixes.

How to Enable Checksums in PostgreSQL
PostgreSQL Database Performance Fri Apr 03 2026

How to Enable Checksums in PostgreSQL

A NetApp study found 400,000+ silent data corruptions across 1.5M drives. Learn how to enable PostgreSQL checksums at init, on existing clusters, and detect corruption before it reaches your backups.

How Do You Check Progress on PostgreSQL's Crash Recovery Process?
PostgreSQL Database Performance Troubleshooting Wed Apr 01 2026

How Do You Check Progress on PostgreSQL's Crash Recovery Process?

PostgreSQL 14's compactify_tuples optimization made crash recovery 2.4x faster. Learn 5 methods to monitor WAL replay progress, from pg_controldata to pg_stat_recovery_prefetch.

PostgreSQL Autovacuum Internals & Tuning Guide
PostgreSQL Database Performance PostgreSQL Query Tuning Troubleshooting Wed Apr 01 2026

PostgreSQL Autovacuum Internals & Tuning Guide

At default settings, a 1 TB PostgreSQL table accumulates up to 200 GB of dead rows before autovacuum triggers. Learn how autovacuum's cost model works and how to tune it for production databases.

PostgreSQL Running Slow? A Step-by-Step Diagnostic Guide
PostgreSQL Database Performance Troubleshooting PostgreSQL Query Tuning Fri Mar 15 2024

PostgreSQL Running Slow? A Step-by-Step Diagnostic Guide

Your PostgreSQL database is slow and you don't know why. This guide walks through a systematic diagnosis process — slow queries, EXPLAIN analysis, index auditing, and autovacuum.

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