ChoosingaDatabase:WhyPostgreSQLFitsMostStartupProducts

PostgreSQL handles standard relational data (users, orders, relationships between entities) reliably, and it also supports JSON fields and full-text search well enough that most products don't need a second, specialized database alongside it. This matters because running one well-understood database is operationally simpler than running two or three specialized ones, especially for a small team without dedicated database expertise.

It's also mature and widely supported across every major cloud provider and hosting platform, which means you're never locked into an obscure or poorly-documented tool as your product grows.

Redis, used alongside a primary database rather than instead of it, is genuinely useful for caching and fast, ephemeral data (session storage, rate limiting) where PostgreSQL's durability guarantees add unnecessary overhead. For workloads with very specific patterns — heavy time-series data, for instance, or a search-heavy product needing advanced text-search capability beyond what PostgreSQL's built-in full-text search offers — a specialized tool alongside PostgreSQL can be the right call.

The mistake to avoid is picking a specialized database as your primary store because of a hypothetical future need, rather than a demonstrated current one — that usually adds operational complexity without a corresponding present-day benefit.

Default to PostgreSQL as your primary database unless you have a specific, demonstrated reason not to. Add Redis alongside it when you have a genuine caching or ephemeral-data need. Reach for anything more specialized only once you have concrete evidence that PostgreSQL's built-in capabilities aren't sufficient for a specific, real requirement.