MongoDB vs PostgreSQL — 6 factors to consider when choosing your database

Choosing between MongoDB and PostgreSQL is one of the most important decisions you'll make for your project. Both databases are mature, reliable and widely used. But they're fundamentally different in how they store, query and scale data. This choice affects your development speed, operational costs and how easily your system can grow. Many developers pick a database based on what's familiar or what's trending. That's fine for small projects. But if you're building something that needs to scale or handle complex data relationships, you need to understand the real differences. This article breaks down six key factors to help you make an informed decision: data model, query complexity, scalability, consistency, performance and backup strategies. 1. Data model and schema flexibility The data model is probably the biggest difference between these two databases. PostgreSQL is a relational database that uses tables with strict schemas. You define columns, types and relationships upfront. Mon