MySQL

In short: One of the most widely used open-source relational database systems — the basis of many classic web stacks (e.g. LAMP: Linux, Apache, MySQL, PHP).

In more detail: MySQL now belongs to Oracle, which led to the MariaDB fork in 2009. Known for easy setup and broad hosting support, but has different strengths/weaknesses in detail than PostgreSQL (e.g. for complex queries or data types).

In Depth

Historical dominance via the LAMP stack

MySQL was released in 1995 and was the standard database for web applications for decades, among other things as the “M” in the classic LAMP stack (Linux, Apache, MySQL, PHP/Perl/Python) — WordPress, many early Facebook systems, and countless web shops ran and still run on MySQL. This enormous adoption still means today: almost every hosting offer, every programming language, and every framework has mature MySQL support, often even as the default preselection for new projects.

MySQL vs. PostgreSQL

Compared directly with PostgreSQL, MySQL is traditionally considered easier to set up and faster for simple, read-heavy workloads, while PostgreSQL often has the edge for complex queries (e.g. with many nested JOINs or window functions), strict data integrity, and advanced data types (native JSON with indexing, arrays, geodata via the PostGIS extension). MySQL was also historically more lenient with faulty data (e.g. it long accepted invalid date values without an error), while PostgreSQL relied on strict standards compliance from the start — a difference that’s converged somewhat over the years, but can still be noticeable in older MySQL installations.

Storage engines

A MySQL peculiarity is the concept of interchangeable storage engines — the actual way data is physically stored is pluggable. InnoDB (the default today) supports transactions and foreign keys, while the older MyISAM was faster for pure read access but offered no transaction safety. This flexibility is a structural difference from PostgreSQL, which uses a unified storage format.

Oracle acquisition and fork

Since Oracle’s acquisition of MySQL’s original owner, Sun Microsystems, in 2009/2010, MySQL’s development direction has been watched critically by some — the concern that a commercial database vendor might deliberately restrict MySQL to protect its own Oracle database product led directly to the founding of the MariaDB fork by the original MySQL developers. Oracle itself emphasises that it continues to maintain MySQL under an open licence, but also publishes a paid “MySQL Enterprise Edition” with additional features.

See also: SQL, MariaDB, PostgreSQL, PHP