Code examples for DynamoDB using AWS SDKs

The following code examples show how to use DynamoDB with an AWS software development kit (SDK).

Basics are code examples that show you how to perform the essential operations within a service.

Actions are code excerpts from larger programs and must be run in context. While actions show you how to call individual service functions, you can see actions in context in their related scenarios.

Scenarios are code examples that show you how to accomplish specific tasks by calling multiple functions within a service or combined with other AWS services.

For a complete list of AWS SDK developer guides and code examples, see Using DynamoDB with an AWS SDK. This topic also includes information about getting started and details about previous SDK versions.

Get started

Hello DynamoDB

The following code examples show how to get started using DynamoDB.

.NET

AWS SDK for .NET

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

using Amazon.DynamoDBv2;
using Amazon.DynamoDBv2.Model;

namespace DynamoDB_Actions;

public static class HelloDynamoDB
{
    static async Task Main(string[] args)
    {
        var dynamoDbClient = new AmazonDynamoDBClient();

        Console.WriteLine($"Hello Amazon Dynamo DB! Following are some of your tables:");
        Console.WriteLine();

        // You can use await and any of the async methods to get a response.
        // Let's get the first five tables.
        var response = await dynamoDbClient.ListTablesAsync(
            new ListTablesRequest()
            {
                Limit = 5
            });

        foreach (var table in response.TableNames)
        {
            Console.WriteLine($"\tTable: {table}");
            Console.WriteLine();
        }
    }
}

• For API details, see ListTables in AWS SDK for .NET API Reference.

C++

SDK for C++

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

Code for the CMakeLists.txt CMake file.

# Set the minimum required version of CMake for this project.
cmake_minimum_required(VERSION 3.13)

# Set the AWS service components used by this project.
set(SERVICE_COMPONENTS dynamodb)

# Set this project's name.
project("hello_dynamodb")

# Set the C++ standard to use to build this target.
# At least C++ 11 is required for the AWS SDK for C++.
set(CMAKE_CXX_STANDARD 11)

# Use the MSVC variable to determine if this is a Windows build.
set(WINDOWS_BUILD ${MSVC})

if (WINDOWS_BUILD) # Set the location where CMake can find the installed libraries for the AWS SDK.
    string(REPLACE ";" "/aws-cpp-sdk-all;" SYSTEM_MODULE_PATH "${CMAKE_SYSTEM_PREFIX_PATH}/aws-cpp-sdk-all")
    list(APPEND CMAKE_PREFIX_PATH ${SYSTEM_MODULE_PATH})
endif ()

# Find the AWS SDK for C++ package.
find_package(AWSSDK REQUIRED COMPONENTS ${SERVICE_COMPONENTS})

if (WINDOWS_BUILD AND AWSSDK_INSTALL_AS_SHARED_LIBS)
     # Copy relevant AWS SDK for C++ libraries into the current binary directory for running and debugging.

     # set(BIN_SUB_DIR "/Debug") # if you are building from the command line you may need to uncomment this 
                                    # and set the proper subdirectory to the executables' location.

     AWSSDK_CPY_DYN_LIBS(SERVICE_COMPONENTS "" ${CMAKE_CURRENT_BINARY_DIR}${BIN_SUB_DIR})
endif ()

add_executable(${PROJECT_NAME}
        hello_dynamodb.cpp)

target_link_libraries(${PROJECT_NAME}
        ${AWSSDK_LINK_LIBRARIES})

Code for the hello_dynamodb.cpp source file.

#include <aws/core/Aws.h>
#include <aws/dynamodb/DynamoDBClient.h>
#include <aws/dynamodb/model/ListTablesRequest.h>
#include <iostream>

/*
 *  A "Hello DynamoDB" starter application which initializes an Amazon DynamoDB (DynamoDB) client and lists the
 *  DynamoDB tables.
 *
 *  main function
 *
 *  Usage: 'hello_dynamodb'
 *
 */

int main(int argc, char **argv) {
    Aws::SDKOptions options;
    // Optionally change the log level for debugging.
//   options.loggingOptions.logLevel = Utils::Logging::LogLevel::Debug;
    Aws::InitAPI(options); // Should only be called once.

    int result = 0;
    {
        Aws::Client::ClientConfiguration clientConfig;
        // Optional: Set to the AWS Region (overrides config file).
        // clientConfig.region = "us-east-1";

        Aws::DynamoDB::DynamoDBClient dynamodbClient(clientConfig);
        Aws::DynamoDB::Model::ListTablesRequest listTablesRequest;
        listTablesRequest.SetLimit(50);
        do {
            const Aws::DynamoDB::Model::ListTablesOutcome &outcome = dynamodbClient.ListTables(
                    listTablesRequest);
            if (!outcome.IsSuccess()) {
                std::cout << "Error: " << outcome.GetError().GetMessage() << std::endl;
                result = 1;
                break;
            }

            for (const auto &tableName: outcome.GetResult().GetTableNames()) {
                std::cout << tableName << std::endl;
            }

            listTablesRequest.SetExclusiveStartTableName(
                    outcome.GetResult().GetLastEvaluatedTableName());

        } while (!listTablesRequest.GetExclusiveStartTableName().empty());
    }


    Aws::ShutdownAPI(options); // Should only be called once.
    return result;
}

• For API details, see ListTables in AWS SDK for C++ API Reference.

Java

SDK for Java 2.x

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
import software.amazon.awssdk.services.dynamodb.model.DynamoDbException;
import software.amazon.awssdk.services.dynamodb.model.ListTablesRequest;
import software.amazon.awssdk.services.dynamodb.model.ListTablesResponse;
import java.util.List;

/**
 * Before running this Java V2 code example, set up your development
 * environment, including your credentials.
 *
 * For more information, see the following documentation topic:
 *
 * https://docs.aws.amazon.com/sdk-for-java/latest/developer-guide/get-started.html
 */
public class ListTables {
    public static void main(String[] args) {
        System.out.println("Listing your Amazon DynamoDB tables:\n");
        Region region = Region.US_EAST_1;
        DynamoDbClient ddb = DynamoDbClient.builder()
                .region(region)
                .build();
        listAllTables(ddb);
        ddb.close();
    }

    public static void listAllTables(DynamoDbClient ddb) {
        boolean moreTables = true;
        String lastName = null;

        while (moreTables) {
            try {
                ListTablesResponse response = null;
                if (lastName == null) {
                    ListTablesRequest request = ListTablesRequest.builder().build();
                    response = ddb.listTables(request);
                } else {
                    ListTablesRequest request = ListTablesRequest.builder()
                            .exclusiveStartTableName(lastName).build();
                    response = ddb.listTables(request);
                }

                List<String> tableNames = response.tableNames();
                if (tableNames.size() > 0) {
                    for (String curName : tableNames) {
                        System.out.format("* %s\n", curName);
                    }
                } else {
                    System.out.println("No tables found!");
                    System.exit(0);
                }

                lastName = response.lastEvaluatedTableName();
                if (lastName == null) {
                    moreTables = false;
                }

            } catch (DynamoDbException e) {
                System.err.println(e.getMessage());
                System.exit(1);
            }
        }
        System.out.println("\nDone!");
    }
}

• For API details, see ListTables in AWS SDK for Java 2.x API Reference.

JavaScript

SDK for JavaScript (v3)

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

For more details on working with DynamoDB in AWS SDK for JavaScript, see Programming DynamoDB with JavaScript.

import { ListTablesCommand, DynamoDBClient } from "@aws-sdk/client-dynamodb";

const client = new DynamoDBClient({});

export const main = async () => {
  const command = new ListTablesCommand({});

  const response = await client.send(command);
  console.log(response.TableNames.join("\n"));
  return response;
};

• For API details, see ListTables in AWS SDK for JavaScript API Reference.

Python

SDK for Python (Boto3)

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

import boto3

# Create a DynamoDB client using the default credentials and region
dynamodb = boto3.client("dynamodb")

# Initialize a paginator for the list_tables operation
paginator = dynamodb.get_paginator("list_tables")

# Create a PageIterator from the paginator
page_iterator = paginator.paginate(Limit=10)

# List the tables in the current AWS account
print("Here are the DynamoDB tables in your account:")

# Use pagination to list all tables
table_names = []

for page in page_iterator:
    for table_name in page.get("TableNames", []):
        print(f"- {table_name}")
        table_names.append(table_name)

if not table_names:
    print("You don't have any DynamoDB tables in your account.")
else:
    print(f"\nFound {len(table_names)} tables.")

• For API details, see ListTables in AWS SDK for Python (Boto3) API Reference.

Ruby

SDK for Ruby

Note

There's more on GitHub. Find the complete example and learn how to set up and run in the AWS Code Examples Repository.

require 'aws-sdk-dynamodb'
require 'logger'

# DynamoDBManager is a class responsible for managing DynamoDB operations
# such as listing all tables in the current AWS account.
class DynamoDBManager
  def initialize(client)
    @client = client
    @logger = Logger.new($stdout)
  end

  # Lists and prints all DynamoDB tables in the current AWS account.
  def list_tables
    @logger.info('Here are the DynamoDB tables in your account:')

    paginator = @client.list_tables(limit: 10)
    table_names = []

    paginator.each_page do |page|
      page.table_names.each do |table_name|
        @logger.info("- #{table_name}")
        table_names << table_name
      end
    end

    if table_names.empty?
      @logger.info("You don't have any DynamoDB tables in your account.")
    else
      @logger.info("\nFound #{table_names.length} tables.")
    end
  end
end

if $PROGRAM_NAME == __FILE__
  dynamodb_client = Aws::DynamoDB::Client.new
  manager = DynamoDBManager.new(dynamodb_client)
  manager.list_tables
end

• For API details, see ListTables in AWS SDK for Ruby API Reference.

Code examples

• Basics
  • Hello DynamoDB
  • Learn the basics
  • Actions
    • BatchExecuteStatement
    • BatchGetItem
    • BatchWriteItem
    • CreateTable
    • DeleteItem
    • DeleteTable
    • DescribeTable
    • DescribeTimeToLive
    • ExecuteStatement
    • GetItem
    • ListTables
    • PutItem
    • Query
    • Scan
    • UpdateItem
    • UpdateTable
    • UpdateTimeToLive
• Scenarios
  • Accelerate reads with DAX
  • Build an app to submit data to a DynamoDB table
  • Conditionally update an item's TTL
  • Connect to a local instance
  • Create a REST API to track COVID-19 data
  • Create a messenger application
  • Create a serverless application to manage photos
  • Create a web application to track DynamoDB data
  • Create a websocket chat application
  • Create an item with a TTL
  • Detect PPE in images
  • Invoke a Lambda function from a browser
  • Monitor DynamoDB performance
  • Query a table by using batches of PartiQL statements
  • Query a table using PartiQL
  • Query for TTL items
  • Save EXIF and other image information
  • Update an item's TTL
  • Use API Gateway to invoke a Lambda function
  • Use Step Functions to invoke Lambda functions
  • Use a document model
  • Use a high-level object persistence model
  • Use scheduled events to invoke a Lambda function
• Serverless examples
  • Invoke a Lambda function from a DynamoDB trigger
  • Reporting batch item failures for Lambda functions with a DynamoDB trigger