Both databases are excellent, decades-proven, and will outlive whatever framework you picked this year. In 2026 the industry default has clearly settled on PostgreSQL — here is why, where MySQL still makes sense, and why your schema design matters ten times more than the logo.
Why PostgreSQL became the default
Feature depth that business apps actually use. JSONB columns (structured + flexible data in one place — invaluable for multi-tenant SaaS settings and audit payloads), row-level security (tenant isolation enforced in the database, not just app code), richer indexing (partial, expression, GIN for JSON and full-text), window functions and CTEs that make reporting sane, and pgvector — which in 2026 means your RAG/AI features live in the same database as your business data instead of a separate vector store.
The ecosystem gravity. Supabase, Neon, and the modern managed platforms are Postgres-first (Supabase vs Firebase); most new tooling, extensions, and hiring momentum flow the same direction. Defaults compound.
Where MySQL still fits fine
Existing MySQL estates running well (migration for fashion is technical debt in reverse — cost without benefit), teams with deep MySQL operational experience, WordPress/PHP ecosystems where it is the native choice, and simple read-heavy CRUD workloads where the feature gap never surfaces. MySQL is not a mistake; it is just no longer the default.
The comparison that matters
| Dimension | PostgreSQL | MySQL |
|---|---|---|
| Complex queries/reporting | Stronger | Adequate |
| JSON handling | JSONB — first-class | Functional |
| Tenant isolation (RLS) | Built-in | App-layer |
| AI/vector workloads | pgvector, native | External store |
| Managed hosting momentum | Supabase/Neon/RDS | RDS/PlanetScale |
| Ops familiarity in legacy teams | Growing | Often deeper |
What actually decides your database fate
Schema design, indexing discipline, connection pooling, and backup hygiene — done badly, either database crawls; done well, either serves millions of rows without drama. The choose-boring-technology principle applies: pick Postgres by default, MySQL with reasons, and spend your innovation budget elsewhere.
Our default stack is PostgreSQL via Supabase for exactly these reasons (stack guide). Migrating, choosing, or untangling a slow database? Describe the workload — honest advice within one business day.
Frequently asked questions
Should I choose PostgreSQL or MySQL in 2026?
PostgreSQL by default: JSONB, row-level security for tenant isolation, richer indexing, pgvector for AI features, and the managed-platform momentum (Supabase, Neon). Choose MySQL with reasons — existing estates, deep team experience, or WordPress ecosystems.
Why did PostgreSQL become the industry default?
Feature depth business apps actually use (JSONB, RLS, window functions), plus ecosystem gravity — modern managed platforms and tooling are Postgres-first, and pgvector lets AI/RAG workloads live beside business data instead of in a separate store.
Is MySQL bad for new projects?
No — it's excellent and proven; it's just no longer the default. Simple read-heavy CRUD never surfaces the feature gap. Migrating a well-running MySQL system for fashion is cost without benefit.
Does database choice affect performance most?
Rarely. Schema design, indexing discipline, connection pooling, and backup hygiene decide your fate — either database crawls when these are bad and serves millions of rows when they're good. Spend attention there, not on the logo.