MySQL vs PostgreSQL: Data Model, Performance and Scenario Comparison

MySQL and PostgreSQL are the two most widely used open-source relational databases in the world. Both are ACID-compliant, reliable and fast — but their philosophies and strengths differ. This article compares them on concrete criteria so you can pick the right one for a project.

Quick Comparison

Data Types

PostgreSQL's type repertoire is much wider: ARRAY, JSONB, UUID, CIDR/INET, TSVECTOR, range types, custom domains. In MySQL most of these are either missing or squeezed into VARCHAR.

-- Only possible in PostgreSQL
CREATE TABLE product (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    tags TEXT[] NOT NULL,
    metadata JSONB,
    price_range NUMRANGE,
    ip INET,
    doc TSVECTOR
);
CREATE INDEX idx_tags ON product USING GIN(tags);
CREATE INDEX idx_meta ON product USING GIN(metadata);
CREATE INDEX idx_doc  ON product USING GIN(doc);

JSON Support

JSON fields are common in modern web apps, and PostgreSQL is clearly ahead here. JSONB stores in binary form, you can index it with GIN, and JSONPath operators are rich.

-- PostgreSQL JSONB queries
SELECT name FROM products WHERE metadata @> '{"color":"red"}';
SELECT metadata->>'color' FROM products WHERE metadata ? 'color';
SELECT jsonb_array_elements(metadata->'tags') FROM products;

-- MySQL JSON
SELECT name FROM products WHERE JSON_EXTRACT(metadata, '$.color') = 'red';
-- Functional index required; syntax is clunkier

Performance: It Depends

"Which is faster?" has no single answer. For simple CRUD, MySQL is slightly ahead. For complex queries, window functions, CTEs and JSONB, PostgreSQL wins clearly. Under concurrent writes PostgreSQL's MVCC reduces locking.

Replication and HA

Multi-master setups are easier on MySQL thanks to Group Replication (MGR) and Galera — the WordPress/Magento ecosystem expects it. PostgreSQL needs third-party tools like BDR for multi-master; its single-master async/sync replication and logical replication are excellent.

Ecosystem and Hosting

• MySQL: default on shared hosting, cPanel, Plesk — WordPress, Magento, PrestaShop and phpBB all ship on MySQL
• PostgreSQL: default for Django, Rails and modern Node.js/Go projects — Supabase, Neon and CockroachDB speak the PostgreSQL wire protocol
• Cloud managed: AWS RDS, GCP Cloud SQL and Azure Database support both

Security Notes

• Prepared statements are mandatory on both sides
• PostgreSQL's row-level security (RLS) is excellent for multi-tenant apps
• sql_mode=STRICT_ALL_TABLES on MySQL — prevents silent data loss
• TLS connections are mandatory on both — never plaintext in production

When to Pick Each

Pick MySQL / MariaDB when:

• LAMP-style apps like WordPress, Magento, PrestaShop
• You are on shared hosting
• Write-heavy simple CRUD
• Your DBA team specialises in MySQL
• You want multi-master with Galera

Pick PostgreSQL when:

• Complex queries, analytics and reporting
• Heavy JSON/JSONB usage
• You need GIS via PostGIS
• Multi-tenant apps with row-level security
• Django/Rails/Prisma projects
• Rich type system (array, range, UUID, enum)

Note on MariaDB

MariaDB forked from MySQL in 2009. Most features are still compatible, but the projects have diverged: MariaDB's JSON is an alias for TEXT, and it ships extra storage engines (Aria, ColumnStore). Red Hat and Debian now ship MariaDB in place of MySQL. Application code usually runs unchanged on either.

Conclusion

As of 2026, for a greenfield project without ecosystem constraints, PostgreSQL is the right default. MySQL is still strong and WordPress/Magento cannot be replaced. A good backend engineer should know both deeply.