Choose a Capacity Mode

Choose a Capacity Mode sits at the heart of capacity modes in DynamoDB. This guide walks through the concept step by step, with examples, a cheatsheet, and common mistakes to avoid.

Choose a Capacity Mode Overview

Choose a Capacity Mode is a building block you will reach for often in DynamoDB. It keeps related logic together and makes your intent obvious to reviewers and future maintainers.

When you learn choose a capacity mode properly, you avoid the guesswork that leads to bugs and rework. The example below shows the shape you will use in most real DynamoDB projects.

import { DynamoDBClient } from '@aws-sdk/client-dynamodb';
import { DynamoDBDocumentClient, GetCommand, PutCommand } from '@aws-sdk/lib-dynamodb';

const client = new DynamoDBClient({});
const docClient = DynamoDBDocumentClient.from(client);

// reuse docClient across the module for efficient, typed access
await docClient.send(new PutCommand({ TableName: 'Orders', Item: { pk: '1' } }));

The DynamoDBDocumentClient maps plain JavaScript objects to DynamoDB item format for you.

Choose a Capacity Mode Example

import { DynamoDBClient } from '@aws-sdk/client-dynamodb';
import { DynamoDBDocumentClient } from '@aws-sdk/lib-dynamodb';

const docClient = DynamoDBDocumentClient.from(new DynamoDBClient({}));
// docClient.send(new PutCommand(...)) etc.

Start from a minimal Choose a Capacity Mode example and grow it only as needed.
Keep configuration explicit so Choose a Capacity Mode behaves the same in every environment.
Name things clearly so teammates understand your Choose a Capacity Mode at a glance.
Add tests around Choose a Capacity Mode early to lock in expected behaviour.

Amazon DynamoDB Cheatsheet

Handy DynamoDB (AWS SDK v3) reference related to choose a capacity mode.

Operation	Command	Purpose
Create/replace	`PutCommand`	Write an item
Read one	`GetCommand`	Fetch by primary key
Update	`UpdateCommand`	Modify attributes
Delete	`DeleteCommand`	Remove an item
Query	`QueryCommand`	Efficient key-based read
Scan	`ScanCommand`	Full-table read (avoid)
Transaction	`TransactWriteCommand`	Atomic multi-item writes

How Choose a Capacity Mode Works in DynamoDB

Choose a Capacity Mode builds on DynamoDB's key-value and document model, where every item lives in a partition chosen by its partition key and is optionally ordered by a sort key.

The DynamoDBDocumentClient maps plain JavaScript objects to DynamoDB item format for you.

Design access patterns first, then model keys around them.
Prefer Query over Scan for predictable performance.
Use expressions to read and write only what you need.
Keep items small and avoid hot partitions.

Practical Guidance for Choose a Capacity Mode

In production, choose a capacity mode should be cost-aware and resilient. Right-size capacity, handle throttling with retries, and lean on indexes to support your query patterns.

Concern	Recommendation
Performance	Query by key; avoid table scans
Cost	Use on-demand or right-sized provisioned capacity
Modeling	Design for known access patterns
Reliability	Retry throttled requests with backoff

Common Mistakes

Skipping error handling and edge cases when wiring up choose a capacity mode.
Leaving choose a capacity mode untested, so regressions slip into production.
Over-engineering choose a capacity mode before you actually need the extra flexibility.
Ignoring documentation, which makes choose a capacity mode hard for the next developer to change.

Key Takeaways

Choose a Capacity Mode is a core part of working effectively with DynamoDB.
Start small and keep choose a capacity mode focused on a single responsibility.
Apply consistent patterns so choose a capacity mode scales across your project.
Test and document choose a capacity mode to keep it maintainable over time.

Pro Tip

Pair choose a capacity mode with automated tests from day one. It is far cheaper to catch DynamoDB regressions in CI than in production.