PostgreSQL vs MySQL
Compare PostgreSQL and MySQL databases - features, performance, SQL compliance, extensibility, and use cases to pick the right RDBMS.
Overview
PostgreSQL and MySQL are the two most popular open-source relational database management systems. PostgreSQL emphasizes standards compliance, extensibility, and advanced features, while MySQL focuses on speed, simplicity, and wide adoption. Both are mature, production-ready systems used by organizations of all sizes.
Feature Comparison
| Feature | PostgreSQL | MySQL |
|---|---|---|
| License | PostgreSQL License (permissive) | GPL v2 (with commercial option) |
| SQL Compliance | Highly compliant | Partially compliant |
| ACID Compliance | Full | Full (InnoDB engine) |
| JSON Support | Native JSONB with indexing | JSON type (limited indexing) |
| Full-Text Search | Built-in | Built-in |
| Replication | Logical & streaming | Binary log & group replication |
| Partitioning | Declarative partitioning | Range, list, hash, key |
| Stored Procedures | PL/pgSQL, PL/Python, PL/Perl | SQL, PL/SQL-like |
| Extensions | Rich extension ecosystem | Plugin system |
| MVCC | Native | InnoDB only |
| Window Functions | Full support | Full support (8.0+) |
| CTEs (WITH) | Full, recursive | Full (8.0+) |
| Materialized Views | Yes | No |
| Custom Types | Yes | No |
| GIS/Spatial | PostGIS (advanced) | Basic spatial support |
| Max DB Size | Unlimited | Unlimited |
| Concurrency | MVCC, excellent | Good with InnoDB |
| Default Port | 5432 | 3306 |
PostgreSQL Pros & Cons
Pros:
- Superior SQL standards compliance
- Advanced data types (JSONB, arrays, hstore, ranges)
- Powerful extension system (PostGIS, pg_trgm, TimescaleDB)
- Excellent concurrency handling via MVCC
- Materialized views and advanced indexing (GIN, GiST, BRIN)
- Strong data integrity and constraint support
- Rich procedural language support
Cons:
- Higher memory consumption
- Slower for simple read-heavy workloads
- Steeper learning curve for tuning
- Fewer managed hosting options historically (improving)
- Replication setup can be more complex
MySQL Pros & Cons
Pros:
- Fast for read-heavy workloads
- Simple to set up and administer
- Massive community and ecosystem
- Wide hosting provider support
- Good replication and clustering options
- Lower resource consumption for simple queries
- Excellent tooling (MySQL Workbench, phpMyAdmin)
Cons:
- Weaker SQL standards compliance
- Limited data type flexibility
- No materialized views
- Partial support for advanced features (historically)
- Oracle ownership concerns for some users
- Less extensible than PostgreSQL
When to Use PostgreSQL
- Complex queries with advanced SQL features (CTEs, window functions, lateral joins)
- Applications requiring JSONB document storage alongside relational data
- Geospatial applications (with PostGIS)
- Data warehousing and analytics workloads
- Projects needing custom types, functions, or extensions
- Write-heavy workloads with complex transactions
- Strict data integrity requirements
When to Use MySQL
- Simple CRUD applications with read-heavy workloads
- WordPress, Drupal, and other CMS platforms
- Projects where ease of setup and administration matters most
- Applications already tied to MySQL ecosystem
- High-volume web applications with simple queries
- Environments with limited DBA expertise
- Legacy systems with MySQL dependencies
Verdict
Choose PostgreSQL for complex applications requiring advanced SQL features, extensibility, and strong data integrity. It excels at handling diverse data types and complex queries.
Choose MySQL for straightforward web applications, CMS platforms, and read-heavy workloads where simplicity and speed for basic operations are priorities.
For new projects without specific constraints, PostgreSQL is generally the stronger choice due to its feature richness and standards compliance. MySQL remains excellent for simpler use cases and has a larger ecosystem of compatible tools and hosting providers.