The two biggest open-source relational databases. Features, performance, and the right choice for your stack.
PG
PostgreSQL
VS
MY
MySQL
Bottom line: PostgreSQL is the more feature-rich, standards-compliant database with superior JSON support, window functions, and extensibility. MySQL is simpler, has wider hosting compatibility, and is faster for basic read-heavy workloads. For new projects in 2026, PostgreSQL is the default choice. For WordPress or legacy PHP hosting, MySQL is still the practical pick.
Our Pick PostgreSQL for features · MySQL for simplicity
Feature Comparison
Feature
PostgreSQL
MySQL
SQL standards compliance
Excellent Win
Good
JSON/JSONB support
Native JSONB with indexing Win
Basic JSON type
Full-text search
Built-in, powerful Win
Built-in, basic
Window functions
Full support Win
Added in 8.0
Simple read performance
Excellent
Faster for simple SELECTs Win
Complex query performance
Superior optimizer Win
Good
Concurrent writes (MVCC)
True MVCC Win
InnoDB MVCC
Extensibility
Extensions (PostGIS, pgvector) Win
Plugins
Hosting compatibility
Growing fast
Available everywhere Win
Replication
Streaming + logical
Built-in, mature Win
Community momentum
Fastest-growing RDBMS Win
Stable, mature
License
PostgreSQL (permissive)
GPL v2 (Oracle)
Managed Cloud Options
PG
PostgreSQL Hosting
SupabaseFree tier
NeonFree tier
AWS RDSFrom ~$15/mo
RailwayUsage-based
MY
MySQL Hosting
PlanetScaleFree tier
AWS RDSFrom ~$15/mo
DigitalOceanFrom $15/mo
Shared hostingIncluded
Pros and Cons
PG
PostgreSQL
Pros
+ Most advanced open-source RDBMS
+ Native JSONB with GIN indexing (document-DB features)
+ PostGIS for geospatial, pgvector for AI embeddings
+ True MVCC for excellent concurrent write performance
+ Permissive license (no Oracle risk)
Cons
− Slightly steeper learning curve
− VACUUM process can be confusing for beginners
− Fewer cheap shared hosting options
MY
MySQL
Pros
+ Simpler to set up and learn
+ Faster for simple read-heavy workloads
+ Available on virtually every hosting provider
+ WordPress and PHP ecosystem standard
Cons
− Owned by Oracle (licensing concerns)
− Weaker JSON and full-text search vs PostgreSQL
− Less extensible, fewer advanced data types
Detailed Analysis
The JSON Question
PostgreSQL's JSONB type with GIN indexing lets you treat your relational database like a document store when you need to. You can index into JSON objects, query nested fields efficiently, and even use JSON path expressions. MySQL added a JSON type in 5.7, but it lacks the indexing depth and query flexibility of PostgreSQL's JSONB.
Extensions: PostgreSQL's Superpower
PostgreSQL's extension system is genuinely unique. PostGIS turns it into a world-class geospatial database. pgvector enables AI vector similarity search. TimescaleDB adds time-series capabilities. pg_trgm powers fuzzy text search. No other RDBMS has this breadth of first-class extensions.
For most new projects in 2026: choose PostgreSQL. It covers everything MySQL does plus advanced features you may need later. Choose MySQL if you are building on WordPress, need the cheapest possible shared hosting, or are maintaining an existing MySQL codebase.
Yes, but it requires migration effort. Tools like pgloader can automate most of the schema and data conversion. The biggest challenges are usually MySQL-specific syntax (e.g., backtick quoting, AUTO_INCREMENT vs SERIAL) and application-level query differences.
MariaDB is a fork of MySQL created by MySQL's original developer after Oracle's acquisition. It is largely compatible with MySQL but has diverged on some features. MariaDB is often used as a drop-in replacement on Linux distributions.
PostgreSQL has become the default database for most modern startups and cloud-native applications. The rise of Supabase, Neon, and Railway has made PostgreSQL hosting as easy as MySQL hosting used to be.