Features of MySQL

ACID · replication · partitioning · JSON · spatial · 50+ storage engines.

Visual explanation diagram · click steps to walk through it

Definition

MySQL's headline features in 2026: ACID transactions (via InnoDB), row-level locking, MVCC, replication (statement + row + GTID), partitioning, JSON column type, spatial data, window functions (8.0+), CTEs, and 50+ storage engines.

How It Works

Most features ship out-of-the-box; some (replication, partitioning) require explicit configuration. Storage engines are pluggable — you mix them per table within the same database.

Example

sql
SELECT 'Hello, MySQL!' AS greeting;

Expected Output

(Run in MySQL Workbench or `mysql` CLI — values depend on your data.)

Why It Matters

The breadth of features means MySQL can handle anything from a personal blog to a billion-row OLTP shard. Every backend interview will probe at least 3-4 of these.

Key Takeaways

ACID transactions via InnoDB.
Replication — async, semi-sync, group replication (multi-primary).
JSON column type — query, index, and update JSON natively.
Window functions + CTEs (since MySQL 8.0).
Spatial — POINT, POLYGON, GEOMETRY with R-tree indexes.

Interview Questions

Practice Questions

Create a table with a metadata JSON column and query it with ->>'$.country'.
Use ROW_NUMBER() OVER (PARTITION BY user_id ORDER BY created_at) to rank rows.
Set up a basic primary-replica replication between two Docker containers.

Pro Tips

Test your replication failover scenarios in staging — not in prod at 2am.
Use generated columns + indexes to query into JSON efficiently.
Window functions can replace many self-joins — usually faster and clearer.

// Try It Yourself · MySQL Playground

in-browser SQLite · no network

Run any SELECT, INSERT, JOIN or GROUP BY against the seeded users · products · orders tables — your changes are sandboxed and reset whenever you click Reset DB.

// editor · Ctrl + Enter to run

// result

Click Run to see results here.

// see seed schema (3 tables · 8 users · 8 products · 12 orders)

users (id, name, email, country, age, created_at)
products (id, name, price, stock, category)
orders (id, user_id → users.id, product_id → products.id, qty, total, created_at)

// Challenges0 / 6 solved

Each challenge is auto-graded — write the SQL, click Submit answer, and we'll compare your result-set to the canonical one.