---
title: Amazon DynamoDB
description: Fully managed serverless NoSQL database delivering single-digit millisecond performance at any scale.
url: https://www.factualminds.com/glossary/amazon-dynamodb/
publishDate: 2026-06-13
updateDate: 2026-06-13
---

# Amazon DynamoDB

> Fully managed serverless NoSQL database delivering single-digit millisecond performance at any scale.

## Definition

Amazon **DynamoDB** is a fully managed, serverless **NoSQL** database offering single-digit millisecond reads and writes at virtually unlimited scale. Data lives in **tables** of **items** (attribute maps) keyed by a required **partition key** (and optional **sort key**). Schema is schemaless per item, but **access patterns are not** — every query must hit the primary key or a **GSI/LSI** you designed upfront. Capacity modes are **on-demand** (pay per request, instant scale) or **provisioned** with auto scaling and reserved capacity for steady workloads.

**DynamoDB Streams** emit item-level change records for Lambda-driven event architectures. **Global Tables** provide multi-region, multi-active replication with last-writer-wins conflict handling. **DynamoDB zero-ETL integrations to Amazon Redshift** (2024+) replicate table changes into Redshift for analytics without custom CDC pipelines — pair operational DynamoDB with warehouse reporting without duplicating business logic in Glue jobs.

## When to use it

- Known **access patterns** (get by user ID, query orders by user + time range) at high throughput without manual sharding.
- **Serverless** stacks (API Gateway + Lambda + DynamoDB) needing millisecond latency and horizontal scale by default.
- Session stores, gaming state, IoT telemetry, shopping carts, and idempotency token tables.
- **Global Tables** when each region must serve local writes with acceptable eventual consistency semantics.

## When not to use it

- Ad hoc **SQL reporting**, multi-table joins, or ORM-centric CRUD without access-pattern discipline.
- Workloads requiring **strong cross-item transactions** across many partitions frequently — transactions exist but have limits.
- Large blob storage inside items — **400 KB item limit**; store payloads in S3 and keep pointers in DynamoDB.

## Tips

- Start design workshops with **access patterns on paper** (read/write paths, cardinality, hot keys) before creating the first table.
- Use **on-demand** for spiky or unknown traffic; switch to **provisioned + auto scaling + reservations** once daily RCU/WCU stabilize — savings are substantial at steady state.
- Enable **PITR** (35-day window) on production tables — on-demand backups alone miss granular restore-to-time scenarios.
- Watch **hot partitions** via CloudWatch `ConsumedReadCapacityUnits` per key metrics and **Contributor Insights** — celebrity users or sequential IDs cause throttling.
- Leverage **zero-ETL to Redshift** for analytics instead of scanning tables from Lambda cron jobs.

## Gotchas

- **Serious:** Adding a new query pattern late often requires **new GSIs or table redesign** — migrations are doable but painful under live traffic.
- **Serious:** **Hot partition keys** (status=`ACTIVE`, shard=0) throttle the whole table despite high total capacity — design key cardinality deliberately.
- **Regular:** **On-demand mode** during sustained high QPS costs more than well-tuned provisioned — revisit mode quarterly.
- **Regular:** **Global Tables** conflicts resolve last-writer-wins — business logic must tolerate or prevent concurrent updates to the same item across regions.
- **Regular:** **DynamoDB Streams** trim after 24 hours — consumers lagging more than a day lose data permanently.

## Official references

- [DynamoDB zero-ETL integrations](https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/zero-etl.html) — Redshift replication setup.
- [Best practices for designing tables](https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/bp-table-design.html) — keys, GSIs, and hot partitions.

## Related FactualMinds content

- [Amazon RDS](/glossary/amazon-rds/) — when SQL fits better
- [Amazon Redshift](/glossary/amazon-redshift/) — zero-ETL analytics target
- [AWS Serverless Services](/services/aws-serverless/)
- [AWS Migration Services](/services/aws-migration/)
- [Cloud Cost Optimization](/services/aws-cloud-cost-optimization-services/)

## Related AWS Services

- aws-rds-consulting
- aws-serverless
- aws-cloud-cost-optimization-services

## Related Posts

- aws-well-architected-framework-6-pillars-explained

---

*Source: https://www.factualminds.com/glossary/amazon-dynamodb/*