We understand that tackling SQL interviews can feel challenging, but with the right focus, you can master the required knowledge. Structured specifically for the 2026 job market, this comprehensive resource provides 50 real, frequently asked SQL interview questions covering everything from basic definitions and data manipulation to advanced analytical queries and performance optimisation. Section 1: SQL […]

In 2025, MySQL celebrated its 30th anniversary—and to mark the milestone, Oracle University (together with the MySQL Community team) offered free MySQL training and free certification exams from April 20 through July 31, 2025.  The goal was simple: make it easy for developers, DBAs, architects, and newcomers to build practical skills and validate them with […]

I would like to thank AWS Open Source for their support.

For some time, I am maintaining Planet for the MySQL Community, a blog / news aggregator for the MySQL Community/Ecosystem.  I am also maintaining a similar aggregator for the Valkey Community.

Maintaining blog / news aggregators is not free.  It incurs hosting, domain registration, and other costs (in addition to time,

As a MySQL consultant, I keep running into the same two problems: reviewing MySQL configurations and generating realistic test data for validation. So I built two focused MySQL tools to…

The post MySQL Tools for Performance Tuning and Test Data Generation first appeared on Change Is Inevitable.

During any MySQL major version upgrade, especially when moving from 8.0 to 8.4, it’s not just about compatibility checks. Subtle default changes can directly impact MySQL performance tuning, and if…

The post How to fix write latency in MySQL 8.4 Upgrade first appeared on Change Is Inevitable.

MySQL HeatWave Service on Oracle Cloud Infrastructure (OCI) provides built-in telemetry and logging capabilities that help organizations monitor database activity, troubleshoot issues, and maintain operational health. These logs are valuable not only for operations and performance tuning, but also for governance and regulatory compliance, where audit logging can be essential for tracking database activity and […]

Oracle was proud to sponsor and participate in TEDAI San Francisco, a sold-out event that brought together over 1,200 attendees from across industries to explore, debate, and celebrate the transformative potential of artificial intelligence. Through a mix of key panels, a 48-hour hackathon, and thought leadership engagement, Oracle showcased its commitment to responsible AI innovation […]

Introduction

Many MySQL setups begin life with a familiar incantation:

Copy Copied!

innodb_buffer_pool_size = 70% of RAM

…and then nothing changes.

That’s not tuning. That’s a starting guess.

Real tuning starts when the workload pushes back.

Visual Overview

The InnoDB buffer pool is where database performance is quietly decided. It determines whether your workload hums along in memory or drags itself across disk. If you’re not actively observing and tuning it, you’re leaving performance on the table.

This guide walks through how to monitor, understand, and tune the buffer pool using real signals instead of guesswork.

What the Buffer Pool Really Is

The buffer pool isn’t just “memory for MySQL.” It’s a living system under constant pressure:

• A cache of data and indexes
• A write staging area …

Benchmarking MyRocks vs. InnoDB in Memory-Constrained Environments It is a well-known fact in the database world that InnoDB is incredibly fast when the entire database fits into memory. But what happens when your data grows beyond your available RAM? MyRocks, built on RocksDB, is frequently recommended as a superior choice for environments constrained by memory, […]

Speed up your PHP application without changing a single query.

A few days ago I set out to answer a simple question: how much faster can a PHP app go if you drop a SQL cache in front of MySQL — without touching application code? The answer is below. On a four-table join aggregating revenue by category and region, Readyset served the same result 60x faster than MySQL. And all I did was change a port number.

This post walks through exactly what I did, step by step, so you can reproduce it yourself.

What Is Readyset?

Readyset is a SQL-aware caching engine that speaks the native MySQL wire protocol. Your PHP application connects to it the same way it connects to MySQL — same driver, same queries, same credentials. Underneath, Readyset proxies queries to your upstream database and, for the ones you choose to cache, serves …