MySQL vs PostgreSQL: Introduction, Performance Comparison, Use Cases, and Summary

MySQL claims to be the most popular open‑source relational database and is the "M" in the LAMP stack. It was originally developed by MySQL AB, sold to Sun in 2008, and later acquired by Oracle in 2010, resulting in commercial and community editions.

PostgreSQL positions itself as the most advanced open‑source database, originating from the POSTGRES project at the University of California, Berkeley in 1985. It is a fully community‑driven RDBMS released under the permissive BSD/MIT license, offering a single, complete feature set.

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.

Performance Comparison

Test environment:

MySQL:
    - Hardware: 4 cores, 16 GB RAM
    - Version: MySQL 8.0

PostgreSQL:
    - Hardware: 4 cores, 16 GB RAM
    - Version: PostgreSQL 13

The benchmark used primary‑key SELECT, UPDATE, and single‑row INSERT operations. The results lead to several conclusions:

PostgreSQL outperforms MySQL by roughly 2× on SELECT, 4–5× on INSERT, and 5–6× on UPDATE throughput.

Average latency for PostgreSQL is several times lower than MySQL.

For hotspot row updates, MySQL achieves only about 1/8 of PostgreSQL's performance, with latency up to 7× higher.

Applicable Scenarios and How to Choose

MySQL is simpler and enjoys broader popularity, richer documentation, and more extensive tooling, making it suitable for small‑to‑medium enterprises and personal projects where ease of use and community support are priorities.

PostgreSQL excels in complex data structures, advanced applications, and large‑scale datasets. It is also a viable choice for smaller workloads, though its query planner may occasionally select suboptimal indexes.

Summary of Advantages

PostgreSQL delivers significantly better performance in both latency and overall throughput.

Hot‑row updates are dramatically faster in PostgreSQL, especially with HOT UPDATE enabled.

SQL standard compliance and feature completeness are higher in PostgreSQL.

PostgreSQL stores tables as heap files, supporting larger data volumes than MySQL's index‑organized tables.

Physical replication in PostgreSQL offers more reliable consistency and higher replication performance compared to MySQL's logical binlog replication.

PostgreSQL’s built‑in optimistic‑lock version column provides safe concurrent updates without the performance penalties of MySQL’s pessimistic locking.

Summary of Disadvantages

PostgreSQL’s system catalog design is more complex, making certain administrative tasks harder.

Choosing the optimal index can be more error‑prone, and PostgreSQL lacks a direct equivalent to MySQL’s FORCE_INDEX hint.

PostgreSQL requires periodic vacuuming, which must be tuned to the specific workload.