PostgreSQL vs MySQL: When to Choose Each

Welcome dear reader, today we compare two of the most popular open-source relational databases: PostgreSQL and MySQL. If you are starting a new web project, chances are you will have to pick between the two. Both are excellent, mature, and free — but each shines in different scenarios. Let’s find out which one fits your next project.

At re:Software S.L., we create innovative solutions for businesses that aim to digitize their processes and routines, and understanding key concepts of database management systems is part of everyday work.

Table of contents

• What Are PostgreSQL and MySQL and How Do They Differ?
• When to Choose MySQL
• When to Choose PostgreSQL
• Conclusion

What Are PostgreSQL and MySQL and How Do They Differ?

Both engines are relational database management systems (RDBMS) — software that stores data in tables of rows and columns, and lets you query it with SQL. If the term relational is new to you, think of Excel sheets that can be linked together and queried at lightning speed.

The main difference is their philosophy. MySQL is famous for being fast and simple: it powers huge parts of the web, including the WordPress sites you can install on a VPS server following our earlier guide. PostgreSQL, often called Postgres, is famous for being strict and feature-rich: it implements the SQL standard very closely and offers advanced data types and functions out-of-the-box.

When to Choose MySQL

MySQL is a great default choice for classic web applications built with PHP, Laravel, or WordPress. It is often the path of least resistance:

-- MySQL: simple table for a classic web app
CREATE TABLE users (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(100) NOT NULL,
    email VARCHAR(150) NOT NULL UNIQUE
);

Choose MySQL when you need shared hosting compatibility, as virtually every host offers it, when your workload is read-heavy — such as content websites — or when your framework and tooling already assume it. Most Laravel tutorials, including our guide on building your own SaaS, default to a MySQL database.

If you are interested to read more about database optimisation, don’t miss our piece on Understanding MySQL Indexes and Query Optimization.

When to Choose PostgreSQL

PostgreSQL is the better pick when your data or queries get complex. It supports advanced column types such as JSONB, arrays, and geographic data, and it indexes them efficiently:

-- PostgreSQL: JSONB column with an index
CREATE TABLE products (
    id SERIAL PRIMARY KEY,
    name VARCHAR(100) NOT NULL,
    attributes JSONB
);

-- Index the JSON for fast lookups
CREATE INDEX idx_products_attrs ON products USING GIN (attributes);

Choose Postgres for data integrity — it validates data more strictly than MySQL — for complex queries with window functions and CTEs, and for extensibility through extensions like PostGIS. If your application grows into analytics, geolocation, or heavy reporting, Postgres will keep up.

Conclusion

There is no single winner in the PostgreSQL vs MySQL debate. Pick MySQL for classic, read-heavy web apps and the widest hosting support; pick PostgreSQL for complex data, strict integrity, and advanced features. Both will serve you well for years, and switching later is possible — though not always cheap. Leave a comment below with the database you picked for your project, and why!