Simple Primary Key

Simple Primary Key Overview

Simple Primary Key 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 simple primary key 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.

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

Amazon DynamoDB Cheatsheet

Handy DynamoDB (AWS SDK v3) reference related to simple primary key.

How Simple Primary Key Works in DynamoDB

Simple Primary Key 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 Simple Primary Key

In production, simple primary key 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 simple primary key.
• Leaving simple primary key untested, so regressions slip into production.
• Over-engineering simple primary key before you actually need the extra flexibility.
• Ignoring documentation, which makes simple primary key hard for the next developer to change.

Key Takeaways

• Simple Primary Key is a core part of working effectively with DynamoDB.
• Start small and keep simple primary key focused on a single responsibility.
• Apply consistent patterns so simple primary key scales across your project.
• Test and document simple primary key to keep it maintainable over time.