Amazon DynamoDB
- What it is
- Fully managed, serverless NoSQL key-value and document database.
- Single-digit millisecond latency at any scale; no servers, no version upgrades, no capacity planning required.
- Key traits
- Data replicated across 3 AZs automatically; 99.999% availability SLA with Global Tables.
- Capacity modes: on-demand (pay per request, scales instantly) or provisioned (cheaper for predictable traffic).
- Global Tables — active-active multi-Region replication.
- DynamoDB Accelerator (DAX) — in-memory cache dropping reads to microseconds.
- Point-in-time recovery to any second in the last 35 days.
- Not to be confused with
- Amazon RDS / Amazon Aurora — relational, SQL, joins, fixed schema, instance-based.
- Amazon MemoryDB for Redis — in-memory primary database; DynamoDB is disk-backed with an optional cache.
- Exam signal
- “Serverless”, “key-value”, “millisecond latency at any scale”, “flexible schema” → DynamoDB.