What are the advantages of PostgreSQL? Why would you choose DynamoDB over other databases like SQL Server?

PostgreSQL is an open‑source relational database that offers strong ACID compliance, advanced SQL features (window functions, common table expressions, full‑text search), and extensibility through custom data types, operators, and extensions such as PostGIS for geospatial data. It supports JSONB for semi‑structured data, allowing efficient querying of nested documents while still providing relational integrity. Concurrency is handled via MVCC, giving low contention for read‑heavy workloads. The community and ecosystem are mature, with robust tooling for backup, replication, and monitoring.

DynamoDB, on the other hand, is a managed NoSQL key‑value and document store that provides single‑digit millisecond latency at any scale. It automatically partitions data, scales horizontally, and offers on‑demand or provisioned capacity modes. DynamoDB is ideal for workloads with predictable access patterns, high write throughput, or when you need a serverless database that integrates tightly with other AWS services. It also supports global tables for multi‑region replication and built‑in encryption and fine‑grained IAM access.

Choosing PostgreSQL is appropriate when you need relational integrity, complex joins, or transactional guarantees. DynamoDB is preferable for high‑throughput, low‑latency, schema‑flexible workloads where you can tolerate eventual consistency and want a fully managed service that scales automatically.