MySQL is a popular open-source relational database that stores data in tables and speaks SQL. It uses a pluggable storage engine architecture, and the engine you pick decides how rows are stored, locked, and recovered.
Since MySQL 5.5, InnoDB is the default and the right choice for almost everything:
COMMIT/ROLLBACK.-- Engine is chosen per table; check what you have:
SELECT table_name, engine
FROM information_schema.tables
WHERE table_schema = 'shop';
-- +------------+--------+
-- | orders | InnoDB | -- transactional, row locks
-- | old_logs | MyISAM | -- legacy, table locks
-- +------------+--------+
CREATE TABLE orders (id INT PRIMARY KEY) ENGINE = InnoDB; -- be explicit
Choosing the engine is choosing your correctness and concurrency guarantees. For any application that writes data and needs transactions or foreign keys, use InnoDB; reaching for MyISAM today usually means inheriting table locks and no crash safety for no real benefit.
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