MariaDB vs PostgreSQL — 7 differences that matter in 2026

Both MariaDB and PostgreSQL are open source, mature and widely used in production. But they come from different lineages and make different trade-offs. MariaDB forked from MySQL in 2009 and stays close to that heritage. PostgreSQL has been its own thing since the 1980s, growing steadily into one of the most feature-rich relational databases available. If you're choosing between them for a new project or considering a migration, this article covers 7 areas where they actually differ in practice. Just the things that tend to matter when you're making the decision for a real system. 1. SQL standards compliance PostgreSQL has always taken SQL standards seriously. It implements large parts of SQL:2023 and enforces strict type checking out of the box. If your query has a type mismatch or ambiguous expression, PostgreSQL will tell you about it at parse time rather than silently doing something unexpected. MariaDB is more relaxed here. It inherited MySQL's permissive approach where implicit co