Table creation with AWS SDK in DynamoDB

Introduction

We create tables in DynamoDB to store and organize data in the cloud. Tables help keep data safe and easy to find.

When you want to save user information for a web app.

When you need to store product details for an online store.

When you want to keep track of orders or transactions.

When you need a fast and scalable database for your app.

When you want to organize data by categories or keys.

Syntax

DynamoDB

const AWS = require('aws-sdk');
AWS.config.update({ region: 'us-east-1' });
const dynamodb = new AWS.DynamoDB();

const params = {
  TableName: 'YourTableName',
  KeySchema: [
    { AttributeName: 'PrimaryKey', KeyType: 'HASH' }
  ],
  AttributeDefinitions: [
    { AttributeName: 'PrimaryKey', AttributeType: 'S' }
  ],
  ProvisionedThroughput: {
    ReadCapacityUnits: 5,
    WriteCapacityUnits: 5
  }
};

dynamodb.createTable(params, function(err, data) {
  if (err) console.log(err);
  else console.log('Table created:', data);
});

KeySchema defines the primary key for the table.

ProvisionedThroughput sets how much read and write capacity the table has.

Examples

This example creates a table named 'Users' with 'UserId' as the primary key of type string.

DynamoDB

const params = {
  TableName: 'Users',
  KeySchema: [
    { AttributeName: 'UserId', KeyType: 'HASH' }
  ],
  AttributeDefinitions: [
    { AttributeName: 'UserId', AttributeType: 'S' }
  ],
  ProvisionedThroughput: {
    ReadCapacityUnits: 5,
    WriteCapacityUnits: 5
  }
};

This example creates a table named 'Orders' with a composite key: 'OrderId' as the partition key and 'OrderDate' as the sort key.

DynamoDB

const params = {
  TableName: 'Orders',
  KeySchema: [
    { AttributeName: 'OrderId', KeyType: 'HASH' },
    { AttributeName: 'OrderDate', KeyType: 'RANGE' }
  ],
  AttributeDefinitions: [
    { AttributeName: 'OrderId', AttributeType: 'S' },
    { AttributeName: 'OrderDate', AttributeType: 'S' }
  ],
  ProvisionedThroughput: {
    ReadCapacityUnits: 10,
    WriteCapacityUnits: 5
  }
};

Sample Program

This program creates a DynamoDB table named 'Books' with 'ISBN' as the primary key. It sets read and write capacity to 5 units each.

DynamoDB

const AWS = require('aws-sdk');
AWS.config.update({ region: 'us-east-1' });

const dynamodb = new AWS.DynamoDB();

const params = {
  TableName: 'Books',
  KeySchema: [
    { AttributeName: 'ISBN', KeyType: 'HASH' }
  ],
  AttributeDefinitions: [
    { AttributeName: 'ISBN', AttributeType: 'S' }
  ],
  ProvisionedThroughput: {
    ReadCapacityUnits: 5,
    WriteCapacityUnits: 5
  }
};

dynamodb.createTable(params, function(err, data) {
  if (err) {
    console.log('Error:', err.message);
  } else {
    console.log('Table created:', data.TableDescription.TableName);
  }
});

Important Notes

Make sure your AWS credentials and region are set correctly before running the code.

Table creation can take a few seconds; the callback confirms when it's ready.

Use meaningful table and key names to keep your data organized.

Summary

DynamoDB tables store data with a primary key to organize it.

Use AWS SDK to create tables by defining name, keys, and capacity.

Check the output to confirm the table was created successfully.