MySQL vs PostgreSQL: Performance, Use Cases, and Choosing the Right Database

1. Database Overview TL;DR

1.1 MySQL

MySQL claims to be the most popular open‑source database and is one of the leading relational database management systems (RDBMS). It is the “M” in the LAMP stack, and applications built on LAMP typically use MySQL.

Originally developed by MySQL AB, it was sold to Sun in 2008 for $1 billion, and Sun was acquired by Oracle in 2010. Oracle now offers a commercial edition and a community edition; the latter is criticized because Oracle controls its development.

1.2 PostgreSQL

PostgreSQL positions itself as the most advanced open‑source database, an object‑relational DBMS (ORDBMS) derived from the 1985 Berkeley POSTGRES project. It is fully community‑driven and released under a permissive BSD/MIT license, allowing free use, modification, and redistribution with a simple copyright notice.

Note: MySQL hierarchy: Instance → Database → Table PostgreSQL hierarchy: Instance → Database → Schema → Table A schema can be understood as a namespace and does not affect usage.

2. Performance Comparison

Test Environment

MySQL:

Hardware: 4‑core CPU, 16 GB RAM

Version: MySQL 8.0

PostgreSQL:

Hardware: 4‑core CPU, 16 GB RAM

Version: PostgreSQL 13

The benchmark used primary‑key SELECT, UPDATE, and single‑row INSERT operations. Results show:

PostgreSQL delivers roughly twice the SELECT throughput of MySQL, 4–5× higher INSERT performance, and 5–6× higher UPDATE performance.

Average latency of PostgreSQL is several times lower than MySQL.

For hot‑row updates, MySQL achieves only about 1/8 of PostgreSQL’s speed, with latency up to seven times higher.

3. Suitable Scenarios and How to Choose

MySQL is simpler and therefore more popular, with richer documentation and ecosystem support, making it a good fit for small‑to‑medium enterprises and personal projects where ease of use matters.

But this does not mean MySQL is the best choice.

PostgreSQL’s rapid development suggests it is catching up with MySQL, whose popularity appears to be declining.

MySQL Use Cases

Suitable for simple applications such as e‑commerce sites, blogs, and general websites. It can handle data volumes from millions to hundreds of millions of rows, but may struggle under high‑performance demands or complex queries.

PostgreSQL Use Cases

Better suited for complex data structures, advanced applications, and large‑scale datasets. It also works for smaller datasets, though its query planner may sometimes choose suboptimal indexes.

4. Summary

Advantages of PostgreSQL over MySQL

Significantly higher performance in SELECT, INSERT, UPDATE, and overall latency.

Hot‑row updates are an order of magnitude faster thanks to HOT UPDATE.

More complete and standards‑compliant SQL implementation.

Uses heap tables, allowing larger data volumes than MySQL’s index‑organized tables.

Physical replication provides stronger consistency and lower performance impact than MySQL’s logical binlog replication.

Built‑in optimistic‑lock version column works with the default repeatable read isolation level, eliminating the need for explicit locking.

Disadvantages of PostgreSQL compared to MySQL

System catalog design is more complex, making certain administrative tasks harder.

Index selection can be trickier; PostgreSQL lacks a direct equivalent of MySQL’s force_index.

Requires periodic VACUUM maintenance, which must be tuned for specific workloads.