DynamoDB Do's and Don'ts

Do's and Don'ts Overview

At its core, do's and don'ts is about doing one thing well inside your DynamoDB project. Once you understand the pattern, you can apply it consistently across features and teams.

Good do's and don'ts pays off across the whole codebase: fewer surprises, easier testing, and smoother onboarding. The snippet below is a solid starting point.

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.

Do's and Don'ts 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 Do's and Don'ts example and grow it only as needed.
• Keep configuration explicit so Do's and Don'ts behaves the same in every environment.
• Name things clearly so teammates understand your Do's and Don'ts at a glance.
• Add tests around Do's and Don'ts early to lock in expected behaviour.

Amazon DynamoDB Cheatsheet

Handy DynamoDB (AWS SDK v3) reference related to do's and don'ts.

How Do's and Don'ts Works in DynamoDB

Do's and Don'ts 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 Do's and Don'ts

In production, do's and don'ts should be cost-aware and resilient. Right-size capacity, handle throttling with retries, and lean on indexes to support your query patterns.

Common Mistakes

• Skipping error handling and edge cases when wiring up do's and don'ts.
• Leaving do's and don'ts untested, so regressions slip into production.
• Over-engineering do's and don'ts before you actually need the extra flexibility.
• Ignoring documentation, which makes do's and don'ts hard for the next developer to change.

Key Takeaways

• Do's and Don'ts is a core part of working effectively with DynamoDB.
• Start small and keep do's and don'ts focused on a single responsibility.
• Apply consistent patterns so do's and don'ts scales across your project.
• Test and document do's and don'ts to keep it maintainable over time.