A database server stores your application's data – posts, users, orders – and answers queries from your code. MySQL vs MariaDB vs PostgreSQL is the main choice for websites and web apps. This guide explains how they differ and when each makes sense.
Before you start
If you use WordPress, Joomla, Magento or most PHP apps on cPanel hosting, the decision is made for you: they use MySQL-compatible databases, which MdmHost hosting provides through cPanel's MySQL Databases tool.
How a database server works
The database server runs as a service (mysqld/mariadbd or postgres) and listens on a port – 3306 for MySQL/MariaDB, 5432 for PostgreSQL – or a local Unix socket. Applications connect with a username and password, send SQL, and get results. Keeping the database on the same server as the app (via localhost) is simplest and fastest; separate database servers help when load grows.
The big three compared
| MySQL | MariaDB | PostgreSQL | |
|---|---|---|---|
| Origin | Owned by Oracle | Community fork of MySQL by its original authors | Independent open-source project |
| Licence | GPL community edition plus commercial editions | GPL | PostgreSQL licence (permissive) |
| Default engine | InnoDB | InnoDB (plus Aria and others) | Single integrated engine |
| Compatibility | The reference for MySQL apps | Largely drop-in for MySQL apps, diverging over time | Different SQL dialect; apps must support it |
| Strengths | Huge ecosystem, simple replication | Open development, extra storage engines, Galera clustering | Standards compliance, advanced types (JSONB, arrays), extensions such as PostGIS |
| Common on | Many Linux distributions and clouds | cPanel, RHEL-family and Debian defaults | Django, Rails and analytics-heavy apps |
MySQL vs MariaDB
MariaDB began as a fork of MySQL in 2009 and kept the same client protocol, tools and file layout, so most PHP apps run on either without changes. Over time each has added features the other lacks, and very new versions are not always swap-compatible, especially for replication and some JSON functions. For typical websites the choice makes little difference; on cPanel you pick it in WHM.
When PostgreSQL is the better choice
- Your framework recommends it (common with Django and Rails).
- You need complex queries, strict data integrity, rich JSON (JSONB) or geographic data (PostGIS).
- You want powerful extensions and a permissive licence.
It is not a drop-in replacement for MySQL; an app must explicitly support PostgreSQL.
Other database types
- SQLite – a file-based database with no server process; ideal for small apps and development.
- Redis – an in-memory key-value store used for caching, sessions and queues alongside a main database.
- MongoDB – a document database storing JSON-like records, used by some Node.js apps.
How to choose
- Use what your application supports and documents best.
- On shared/cPanel hosting, use MySQL/MariaDB.
- For a new custom app on a VPS, PostgreSQL is a strong default; MySQL/MariaDB is equally valid if your team knows it.
- Add Redis for caching when database load grows.
FAQ: MySQL vs MariaDB vs PostgreSQL
Does WordPress work on MariaDB?
Yes. WordPress supports both MySQL and MariaDB.
Can WordPress use PostgreSQL?
Not officially. WordPress core targets MySQL and MariaDB.
Which database server is fastest?
It depends on the workload and tuning more than the brand. Proper indexes, enough memory for caches and fast NVMe storage matter most.