MongoDB is a document database that stores records as BSON documents and supports queries, aggregation and transactions. Teams can operate Community Server themselves or use MongoDB Atlas hosting. Its data model can suit applications organised around documents, while schema validation, indexes and cross-document requirements still need deliberate design. Atlas Free is a constrained development entry point rather than a promise of unlimited production hosting.
MongoDB
Explore the official product
See the vendor’s current capabilities, product information and plan details.
PostgreSQL is an object-relational database for applications that need SQL transactions, relational constraints and extensible data types. It also supports JSON documents and an extension ecosystem including geospatial tools. Teams can run it themselves or buy a managed service from a hosting provider; the database licence does not include somebody operating backups and upgrades for them.
Vendor-described capabilities; availability can depend on the plan.
✓Document-oriented BSON storage
✓Query and aggregation pipelines
✓Indexes and schema validation
✓Transactions and replication
✓Atlas managed database service
MongoDB pricing considerations
Atlas Free and Community Server
Atlas has free and paid deployment choices; hosting configuration and enabled services affect spend. Community software terms, enterprise support and managed operations should be evaluated separately.
Atlas Free clusters do not expire but have limited scale and capabilities. Self-managed Community Server is available under SSPL terms.