Read an item from a DynamoDB table

        /// <summary>
        /// Gets information about an existing movie from the table.
        /// </summary>
        /// <param name="client">An initialized Amazon DynamoDB client object.</param>
        /// <param name="newMovie">A Movie object containing information about
        /// the movie to retrieve.</param>
        /// <param name="tableName">The name of the table containing the movie.</param>
        /// <returns>A Dictionary object containing information about the item
        /// retrieved.</returns>
        public static async Task<Dictionary<string, AttributeValue>> GetItemAsync(AmazonDynamoDBClient client, Movie newMovie, string tableName)
        {
            var key = new Dictionary<string, AttributeValue>
            {
                ["title"] = new AttributeValue { S = newMovie.Title },
                ["year"] = new AttributeValue { N = newMovie.Year.ToString() },
            };

            var request = new GetItemRequest
            {
                Key = key,
                TableName = tableName,
            };

            var response = await client.GetItemAsync(request);
            return response.Item;
        }

#############################################################################
# function dynamodb_get_item
#
# This function gets an item from a DynamoDB table.
#
# Parameters:
#       -n table_name  -- The name of the table.
#       -k keys  -- Path to json file containing the keys that identify the item to get.
#       [-q query]  -- Optional JMESPath query expression.
#
#  Returns:
#       The item as text output.
#  And:
#       0 - If successful.
#       1 - If it fails.
############################################################################
function dynamodb_get_item() {
  local table_name keys query response
  local option OPTARG # Required to use getopts command in a function.

  # ######################################
  # Function usage explanation
  #######################################
  function usage() {
    echo "function dynamodb_get_item"
    echo "Get an item from a DynamoDB table."
    echo " -n table_name  -- The name of the table."
    echo " -k keys  -- Path to json file containing the keys that identify the item to get."
    echo " [-q query]  -- Optional JMESPath query expression."
    echo ""
  }
  query=""
  while getopts "n:k:q:h" option; do
    case "${option}" in
      n) table_name="${OPTARG}" ;;
      k) keys="${OPTARG}" ;;
      q) query="${OPTARG}" ;;
      h)
        usage
        return 0
        ;;
      \?)
        echo "Invalid parameter"
        usage
        return 1
        ;;
    esac
  done
  export OPTIND=1

  if [[ -z "$table_name" ]]; then
    errecho "ERROR: You must provide a table name with the -n parameter."
    usage
    return 1
  fi

  if [[ -z "$keys" ]]; then
    errecho "ERROR: You must provide a keys json file path the -k parameter."
    usage
    return 1
  fi

  if [[ -n "$query" ]]; then
    response=$(aws dynamodb get-item \
      --table-name "$table_name" \
      --key file://"$keys" \
      --output text \
      --query "$query")
  else
    response=$(
      aws dynamodb get-item \
        --table-name "$table_name" \
        --key file://"$keys"
    )
  fi

  local error_code=${?}

  if [[ $error_code -ne 0 ]]; then
    aws_cli_error_log $error_code
    errecho "ERROR: AWS reports get-item operation failed.$response"
    return 1
  fi

  if [[ -n "$query" ]]; then
    echo "$response" | sed "/^\t/s/\t//1" # Remove initial tab that the JMSEPath query inserts on some strings.
  else
    echo "$response"
  fi

  return 0
}

The utility functions used in this example.

###############################################################################
# function errecho
#
# This function outputs everything sent to it to STDERR (standard error output).
###############################################################################
function errecho() {
  printf "%s\n" "$*" 1>&2
}

##############################################################################
# function aws_cli_error_log()
#
# This function is used to log the error messages from the AWS CLI.
#
# See https://docs.aws.amazon.com/cli/latest/topic/return-codes.html#cli-aws-help-return-codes.
#
# The function expects the following argument:
#         $1 - The error code returned by the AWS CLI.
#
#  Returns:
#          0: - Success.
#
##############################################################################
function aws_cli_error_log() {
  local err_code=$1
  errecho "Error code : $err_code"
  if [ "$err_code" == 1 ]; then
    errecho "  One or more S3 transfers failed."
  elif [ "$err_code" == 2 ]; then
    errecho "  Command line failed to parse."
  elif [ "$err_code" == 130 ]; then
    errecho "  Process received SIGINT."
  elif [ "$err_code" == 252 ]; then
    errecho "  Command syntax invalid."
  elif [ "$err_code" == 253 ]; then
    errecho "  The system environment or configuration was invalid."
  elif [ "$err_code" == 254 ]; then
    errecho "  The service returned an error."
  elif [ "$err_code" == 255 ]; then
    errecho "  255 is a catch-all error."
  fi

  return 0
}

//! Get an item from an Amazon DynamoDB table.
/*!
  \sa getItem()
  \param tableName: The table name.
  \param partitionKey: The partition key.
  \param partitionValue: The value for the partition key.
  \param clientConfiguration: AWS client configuration.
  \return bool: Function succeeded.
 */

bool AwsDoc::DynamoDB::getItem(const Aws::String &tableName,
                               const Aws::String &partitionKey,
                               const Aws::String &partitionValue,
                               const Aws::Client::ClientConfiguration &clientConfiguration) {
    Aws::DynamoDB::DynamoDBClient dynamoClient(clientConfiguration);
    Aws::DynamoDB::Model::GetItemRequest request;

    // Set up the request.
    request.SetTableName(tableName);
    request.AddKey(partitionKey,
                   Aws::DynamoDB::Model::AttributeValue().SetS(partitionValue));

    // Retrieve the item's fields and values.
    const Aws::DynamoDB::Model::GetItemOutcome &outcome = dynamoClient.GetItem(request);
    if (outcome.IsSuccess()) {
        // Reference the retrieved fields/values.
        const Aws::Map<Aws::String, Aws::DynamoDB::Model::AttributeValue> &item = outcome.GetResult().GetItem();
        if (!item.empty()) {
            // Output each retrieved field and its value.
            for (const auto &i: item)
                std::cout << "Values: " << i.first << ": " << i.second.GetS()
                          << std::endl;
        }
        else {
            std::cout << "No item found with the key " << partitionKey << std::endl;
        }
    }
    else {
        std::cerr << "Failed to get item: " << outcome.GetError().GetMessage();
    }

    return outcome.IsSuccess();
}

// TableBasics encapsulates the Amazon DynamoDB service actions used in the examples.
// It contains a DynamoDB service client that is used to act on the specified table.
type TableBasics struct {
	DynamoDbClient *dynamodb.Client
	TableName      string
}



// GetMovie gets movie data from the DynamoDB table by using the primary composite key
// made of title and year.
func (basics TableBasics) GetMovie(title string, year int) (Movie, error) {
	movie := Movie{Title: title, Year: year}
	response, err := basics.DynamoDbClient.GetItem(context.TODO(), &dynamodb.GetItemInput{
		Key: movie.GetKey(), TableName: aws.String(basics.TableName),
	})
	if err != nil {
		log.Printf("Couldn't get info about %v. Here's why: %v\n", title, err)
	} else {
		err = attributevalue.UnmarshalMap(response.Item, &movie)
		if err != nil {
			log.Printf("Couldn't unmarshal response. Here's why: %v\n", err)
		}
	}
	return movie, err
}

Gets an item from a table by using the DynamoDbClient.

    public static void getDynamoDBItem(DynamoDbClient ddb,String tableName,String key,String keyVal ) {
        HashMap<String,AttributeValue> keyToGet = new HashMap<>();
        keyToGet.put(key, AttributeValue.builder()
            .s(keyVal)
            .build());

        GetItemRequest request = GetItemRequest.builder()
            .key(keyToGet)
            .tableName(tableName)
            .build();

        try {
            // If there is no matching item, GetItem does not return any data.
            Map<String,AttributeValue> returnedItem = ddb.getItem(request).item();
            if (returnedItem.isEmpty())
                System.out.format("No item found with the key %s!\n", key);
            else {
                Set<String> keys = returnedItem.keySet();
                System.out.println("Amazon DynamoDB table attributes: \n");
                for (String key1 : keys) {
                    System.out.format("%s: %s\n", key1, returnedItem.get(key1).toString());
                }
            }

        } catch (DynamoDbException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
    }

This example uses the document client to simplify working with items in DynamoDB. For API details see GetCommand.

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

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

export const main = async () => {
  const command = new GetCommand({
    TableName: "AngryAnimals",
    Key: {
      CommonName: "Shoebill"
    }
  });

  const response = await docClient.send(command);
  console.log(response);
  return response;
};

Get an item from a table.

// Load the AWS SDK for Node.js
var AWS = require('aws-sdk');
// Set the region 
AWS.config.update({region: 'REGION'});

// Create the DynamoDB service object
var ddb = new AWS.DynamoDB({apiVersion: '2012-08-10'});

var params = {
  TableName: 'TABLE',
  Key: {
    'KEY_NAME': {N: '001'}
  },
  ProjectionExpression: 'ATTRIBUTE_NAME'
};

// Call DynamoDB to read the item from the table
ddb.getItem(params, function(err, data) {
  if (err) {
    console.log("Error", err);
  } else {
    console.log("Success", data.Item);
  }
});

Get an item from a table using the DynamoDB document client.

// Load the AWS SDK for Node.js
var AWS = require('aws-sdk');
// Set the region 
AWS.config.update({region: 'REGION'});

// Create DynamoDB document client
var docClient = new AWS.DynamoDB.DocumentClient({apiVersion: '2012-08-10'});

var params = {
 TableName: 'EPISODES_TABLE',
 Key: {'KEY_NAME': VALUE}
};

docClient.get(params, function(err, data) {
  if (err) {
    console.log("Error", err);
  } else {
    console.log("Success", data.Item);
  }
});

suspend fun getSpecificItem(tableNameVal: String, keyName: String, keyVal: String) {

    val keyToGet = mutableMapOf<String, AttributeValue>()
    keyToGet[keyName] = AttributeValue.S(keyVal)

    val request = GetItemRequest {
        key = keyToGet
        tableName = tableNameVal
    }

    DynamoDbClient { region = "us-east-1" }.use { ddb ->
        val returnedItem = ddb.getItem(request)
        val numbersMap = returnedItem.item
        numbersMap?.forEach { key1 ->
            println(key1.key)
            println(key1.value)
        }
    }
}

        $movie = $service->getItemByKey($tableName, $key);
        echo "\nThe movie {$movie['Item']['title']['S']} was released in {$movie['Item']['year']['N']}.\n";

    public function getItemByKey(string $tableName, array $key)
    {
        return $this->dynamoDbClient->getItem([
            'Key' => $key['Item'],
            'TableName' => $tableName,
        ]);
    }

class Movies:
    """Encapsulates an Amazon DynamoDB table of movie data."""
    def __init__(self, dyn_resource):
        """
        :param dyn_resource: A Boto3 DynamoDB resource.
        """
        self.dyn_resource = dyn_resource
        # The table variable is set during the scenario in the call to
        # 'exists' if the table exists. Otherwise, it is set by 'create_table'.
        self.table = None

    def get_movie(self, title, year):
        """
        Gets movie data from the table for a specific movie.

        :param title: The title of the movie.
        :param year: The release year of the movie.
        :return: The data about the requested movie.
        """
        try:
            response = self.table.get_item(Key={'year': year, 'title': title})
        except ClientError as err:
            logger.error(
                "Couldn't get movie %s from table %s. Here's why: %s: %s",
                title, self.table.name,
                err.response['Error']['Code'], err.response['Error']['Message'])
            raise
        else:
            return response['Item']

class DynamoDBBasics
  attr_reader :dynamo_resource
  attr_reader :table

  def initialize(table_name)
    client = Aws::DynamoDB::Client.new(region: "us-east-1")
    @dynamo_resource = Aws::DynamoDB::Resource.new(client: client)
    @table = @dynamo_resource.table(table_name)
  end

  # Gets movie data from the table for a specific movie.
  #
  # @param title [String] The title of the movie.
  # @param year [Integer] The release year of the movie.
  # @return [Hash] The data about the requested movie.
  def get_item(title, year)
    @table.get_item(key: {"year" => year, "title" => title})
  rescue Aws::DynamoDB::Errors::ServiceError => e
    puts("Couldn't get movie #{title} (#{year}) from table #{@table.name}:\n")
    puts("\t#{e.code}: #{e.message}")
    raise
  end

    /// Return a `Movie` record describing the specified movie from the Amazon
    /// DynamoDB table.
    ///
    /// - Parameters:
    ///   - title: The movie's title (`String`).
    ///   - year: The movie's release year (`Int`).
    ///
    /// - Throws: `MoviesError.ItemNotFound` if the movie isn't in the table.
    ///
    /// - Returns: A `Movie` record with the movie's details.
    func get(title: String, year: Int) async throws -> Movie {
        guard let client = self.ddbClient else {
            throw MoviesError.UninitializedClient
        }

        let input = GetItemInput(
            key: [
                "year": .n(String(year)),
                "title": .s(title)
            ],
            tableName: self.tableName
        )
        let output = try await client.getItem(input: input)
        guard let item = output.item else {
            throw MoviesError.ItemNotFound
        }

        let movie = try Movie(withItem: item)
        return movie
    }