PostgreSQL vs MySQL: Which Open-Source Database Is Right for You?

Q: How do I migrate data from PostgreSQL to MySQL?

Use pg_dump to export your PostgreSQL data (plain SQL or custom format), then convert the schema and data types using a tool like pgloader, which can connect directly to both databases and handle the conversion in one pass. For smaller databases, exporting tables to CSV with COPY and importing them with MySQL's LOAD DATA INFILE also works, but you'll need to manually recreate indexes, constraints, and sequences as MySQL AUTO_INCREMENT columns.

Q: What features do I lose moving from PostgreSQL to MySQL?

You'll lose native JSONB with indexed queries (MySQL's JSON type is less optimized), full recursive CTE support, and any PostGIS geospatial functionality since MySQL has no direct equivalent. Custom functions written in PL/pgSQL, array data types, and advanced window function usage may also need to be rewritten or dropped.

Q: Is MySQL's free tier enough for a small team?

Yes — MySQL Community Edition is fully free with no usage caps, seat limits, or feature restrictions, so a small team can run it in production indefinitely at zero licensing cost. You'll only pay for hosting/infrastructure (or a managed service like Amazon RDS or PlanetScale) if you don't want to self-manage the server.

Q: Will my existing tools and integrations still work with MySQL?

Most ORMs (Prisma, Sequelize, Django ORM, ActiveRecord) and BI tools (Metabase, Tableau, Looker) support both databases, so switching the connector is usually a config change rather than a rewrite. However, any raw SQL using PostgreSQL-specific syntax (JSONB operators, arrays, RETURNING clauses in some drivers) will need to be rewritten for MySQL's dialect.

Q: Does switching to MySQL actually save money long-term?

Both are free open-source software, so there's no licensing cost difference — savings, if any, come from lower resource usage, since MySQL typically needs less CPU/RAM for simple read-heavy workloads. If you're on managed hosting, compare instance pricing for both engines directly (e.g., AWS RDS charges similarly for Postgres and MySQL instances of the same size), since the database engine itself isn't usually the cost driver.

Compare PostgreSQL and MySQL, two leading open-source relational databases. Both are completely free, but differ in features, performance, and complexity. See which fits your project.

Updated 2026-09 · 2026

PostgreSQL

Advanced open-source relational database with full SQL compliance

Freeforever

Strengths

+Full ACID compliance and advanced SQL features (CTEs, window functions, JSON)
+Extensible architecture with custom functions, data types, and extensions
+Superior handling of complex queries and concurrent writes

Weaknesses

-Steeper learning curve for beginners
-More resource-intensive than MySQL for simple queries
-Smaller ecosystem of third-party tools compared to MySQL

Best for

Complex applications requiring advanced SQL features, data warehousing, geospatial data (PostGIS), and projects prioritizing data integrity over raw speed

MySQL

Fast, reliable open-source database powering millions of websites

Freeforever

Strengths

+Excellent read performance and speed for simple queries
+Easy to learn and set up, beginner-friendly
+Massive ecosystem with extensive third-party tool support

Weaknesses

-Less strict about data integrity by default (depends on storage engine)
-Limited support for advanced SQL features compared to PostgreSQL
-Owned by Oracle, raising concerns about long-term open-source commitment

Best for

Web applications, content management systems (WordPress, Drupal), read-heavy workloads, and projects prioritizing simplicity and speed over advanced features

Feature Comparison

Feature	PostgreSQL	MySQL
License & Cost	PostgreSQL License (MIT-style), completely free	GPL v2, completely free (Community Edition)
ACID Compliance	Full ACID compliance across all operations	ACID compliant with InnoDB engine (default since 5.5)
JSON Support	Native JSON and JSONB with indexing and querying	JSON support added in 5.7, less feature-rich
Full-Text Search	Built-in full-text search with multiple languages	Built-in full-text search, simpler implementation
Replication	Streaming replication, logical replication (more complex)	Master-slave replication (simpler setup)
Concurrency	MVCC (Multi-Version Concurrency Control), excellent for writes	Row-level locking, better for read-heavy workloads
Extensibility	Highly extensible (custom functions, types, extensions like PostGIS)	Limited extensibility, plugin architecture
Window Functions	Full support since version 8.4	Added in version 8.0 (2018)
Common Table Expressions (CTEs)	Full support including recursive CTEs	Added in version 8.0, less optimized
Storage Size	Generally larger database size due to MVCC	More compact storage for similar data
Community & Ecosystem	Strong community, growing ecosystem	Massive ecosystem, more third-party tools
Performance	Better for complex queries and write-heavy workloads	Faster for simple queries and read-heavy workloads

The Verdict

Both databases are completely free and production-ready. Choose PostgreSQL if you need advanced SQL features, complex queries, or strong data integrity guarantees. Choose MySQL if you're building a simple web application, prioritize ease of use, or need maximum read performance with a simpler setup. For most modern applications requiring flexibility and growth, PostgreSQL is the better long-term choice.

How to switch from PostgreSQL to MySQL

1Export your PostgreSQL database using pg_dump (e.g., pg_dump --format=plain --no-owner --no-privileges dbname > dump.sql), or export individual tables to CSV with the COPY command for a more controlled, table-by-table migration.
2Convert the schema and data types using pgloader, which maps PostgreSQL-specific types (like SERIAL, ARRAY, and JSONB) to their closest MySQL equivalents (AUTO_INCREMENT, JSON, TEXT) automatically, or do it manually for small schemas.
3Import the converted SQL into MySQL using the mysql command-line client (mysql -u user -p dbname < converted_dump.sql) or LOAD DATA INFILE for CSV-based imports, then verify row counts and spot-check data against the original.
4Rewrite any PostgreSQL-specific SQL — recursive CTEs, JSONB operators, array columns, PL/pgSQL functions, and PostGIS queries — since these either don't exist in MySQL or use different syntax.
5Update connection strings, ORM configuration (dialect: 'mysql' in Prisma/Sequelize/TypeORM), and driver dependencies in your application code, then run your full test suite against the new database.
6Run both databases in parallel for a short period, replicating writes or comparing outputs, before cutting over DNS/connection endpoints and decommissioning the old PostgreSQL instance.

PostgreSQL vs MySQL: common questions

How do I migrate data from PostgreSQL to MySQL?+

Use pg_dump to export your PostgreSQL data (plain SQL or custom format), then convert the schema and data types using a tool like pgloader, which can connect directly to both databases and handle the conversion in one pass. For smaller databases, exporting tables to CSV with COPY and importing them with MySQL's LOAD DATA INFILE also works, but you'll need to manually recreate indexes, constraints, and sequences as MySQL AUTO_INCREMENT columns.

What features do I lose moving from PostgreSQL to MySQL?+

You'll lose native JSONB with indexed queries (MySQL's JSON type is less optimized), full recursive CTE support, and any PostGIS geospatial functionality since MySQL has no direct equivalent. Custom functions written in PL/pgSQL, array data types, and advanced window function usage may also need to be rewritten or dropped.

Is MySQL's free tier enough for a small team?+

Yes — MySQL Community Edition is fully free with no usage caps, seat limits, or feature restrictions, so a small team can run it in production indefinitely at zero licensing cost. You'll only pay for hosting/infrastructure (or a managed service like Amazon RDS or PlanetScale) if you don't want to self-manage the server.

Will my existing tools and integrations still work with MySQL?+

Most ORMs (Prisma, Sequelize, Django ORM, ActiveRecord) and BI tools (Metabase, Tableau, Looker) support both databases, so switching the connector is usually a config change rather than a rewrite. However, any raw SQL using PostgreSQL-specific syntax (JSONB operators, arrays, RETURNING clauses in some drivers) will need to be rewritten for MySQL's dialect.

Does switching to MySQL actually save money long-term?+

Both are free open-source software, so there's no licensing cost difference — savings, if any, come from lower resource usage, since MySQL typically needs less CPU/RAM for simple read-heavy workloads. If you're on managed hosting, compare instance pricing for both engines directly (e.g., AWS RDS charges similarly for Postgres and MySQL instances of the same size), since the database engine itself isn't usually the cost driver.