Update an item in a DynamoDB table using an Amazon SDK - Amazon DynamoDB
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Update an item in a DynamoDB table using an Amazon SDK

The following code examples show how to update an item in a DynamoDB table.

.NET
Amazon SDK for .NET
Note

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

/// <summary> /// Updates an existing item in the movies table. /// </summary> /// <param name="client">An initialized Amazon DynamoDB client object.</param> /// <param name="newMovie">A Movie object containing information for /// the movie to update.</param> /// <param name="newInfo">A MovieInfo object that contains the /// information that will be changed.</param> /// <param name="tableName">The name of the table that contains the movie.</param> /// <returns>A Boolean value that indicates the success of the operation.</returns> public static async Task<bool> UpdateItemAsync( AmazonDynamoDBClient client, Movie newMovie, MovieInfo newInfo, string tableName) { var key = new Dictionary<string, AttributeValue> { ["title"] = new AttributeValue { S = newMovie.Title }, ["year"] = new AttributeValue { N = newMovie.Year.ToString() }, }; var updates = new Dictionary<string, AttributeValueUpdate> { ["info.plot"] = new AttributeValueUpdate { Action = AttributeAction.PUT, Value = new AttributeValue { S = newInfo.Plot }, }, ["info.rating"] = new AttributeValueUpdate { Action = AttributeAction.PUT, Value = new AttributeValue { N = newInfo.Rank.ToString() }, }, }; var request = new UpdateItemRequest { AttributeUpdates = updates, Key = key, TableName = tableName, }; var response = await client.UpdateItemAsync(request); return response.HttpStatusCode == System.Net.HttpStatusCode.OK; }
  • For API details, see UpdateItem in Amazon 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 Amazon Code Examples Repository.

Aws::Client::ClientConfiguration clientConfig; Aws::DynamoDB::DynamoDBClient dynamoClient(clientConfig); // *** Define UpdateItem request arguments // Define TableName argument. Aws::DynamoDB::Model::UpdateItemRequest request; request.SetTableName(tableName); // Define KeyName argument. Aws::DynamoDB::Model::AttributeValue attribValue; attribValue.SetS(keyValue); request.AddKey("id", attribValue); // Construct the SET update expression argument. Aws::String update_expression("SET #a = :valueA"); request.SetUpdateExpression(update_expression); // Parse the attribute name and value. Syntax: "name=value". auto parsed = Aws::Utils::StringUtils::Split(attributeNameAndValue, '='); if (parsed.size() != 2) { std::cout << "Invalid argument syntax: " << attributeNameAndValue << USAGE; return 1; } // Construct attribute name argument // Note: Setting the ExpressionAttributeNames argument is required only // when the name is a reserved word, such as "default". Otherwise, the // name can be included in the update_expression, as in // "SET MyAttributeName = :valueA" Aws::Map<Aws::String, Aws::String> expressionAttributeNames; expressionAttributeNames["#a"] = parsed[0]; request.SetExpressionAttributeNames(expressionAttributeNames); // Construct attribute value argument. Aws::DynamoDB::Model::AttributeValue attributeUpdatedValue; attributeUpdatedValue.SetS(parsed[1]); Aws::Map<Aws::String, Aws::DynamoDB::Model::AttributeValue> expressionAttributeValues; expressionAttributeValues[":valueA"] = attributeUpdatedValue; request.SetExpressionAttributeValues(expressionAttributeValues); // Update the item. const Aws::DynamoDB::Model::UpdateItemOutcome& result = dynamoClient.UpdateItem(request); if (!result.IsSuccess()) { std::cout << result.GetError().GetMessage() << std::endl; return 1; } std::cout << "Item was updated" << std::endl;
  • For API details, see UpdateItem in Amazon SDK for C++ API Reference.

Go
SDK for Go V2
Note

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

// 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 } // UpdateMovie updates the rating and plot of a movie that already exists in the // DynamoDB table. This function uses the `expression` package to build the update // expression. func (basics TableBasics) UpdateMovie(movie Movie) (map[string]map[string]interface{}, error) { var err error var response *dynamodb.UpdateItemOutput var attributeMap map[string]map[string]interface{} update := expression.Set(expression.Name("info.rating"), expression.Value(movie.Info["rating"])) update.Set(expression.Name("info.plot"), expression.Value(movie.Info["plot"])) expr, err := expression.NewBuilder().WithUpdate(update).Build() if err != nil { log.Printf("Couldn't build expression for update. Here's why: %v\n", err) } else { response, err = basics.DynamoDbClient.UpdateItem(context.TODO(), &dynamodb.UpdateItemInput{ TableName: aws.String(basics.TableName), Key: movie.GetKey(), ExpressionAttributeNames: expr.Names(), ExpressionAttributeValues: expr.Values(), UpdateExpression: expr.Update(), ReturnValues: types.ReturnValueUpdatedNew, }) if err != nil { log.Printf("Couldn't update movie %v. Here's why: %v\n", movie.Title, err) } else { err = attributevalue.UnmarshalMap(response.Attributes, &attributeMap) if err != nil { log.Printf("Couldn't unmarshall update response. Here's why: %v\n", err) } } } return attributeMap, err }
  • For API details, see UpdateItem in Amazon SDK for Go 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 Amazon Code Examples Repository.

Updates an item located in a table by using the enhanced client.

public static String modifyItem(DynamoDbEnhancedClient enhancedClient, String keyVal, String email) { try { DynamoDbTable<Customer> mappedTable = enhancedClient.table("Customer", TableSchema.fromBean(Customer.class)); Key key = Key.builder() .partitionValue(keyVal) .build(); // Get the item by using the key and update the email value. Customer customerRec = mappedTable.getItem(r->r.key(key)); customerRec.setEmail(email); mappedTable.updateItem(customerRec); return customerRec.getEmail(); } catch (DynamoDbException e) { System.err.println(e.getMessage()); System.exit(1); } return ""; }
  • For API details, see UpdateItem in Amazon 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 Amazon Code Examples Repository.

Create the client.

// Create the DynamoDB service client module using ES6 syntax. import { DynamoDBClient } from "@aws-sdk/client-dynamodb"; // Set the AWS Region. export const REGION = "REGION"; // For example, "us-east-1". // Create an Amazon DynamoDB service client object. export const ddbClient = new DynamoDBClient({ region: REGION });

Create the DynamoDB document client.

// Create a service client module using ES6 syntax. import { DynamoDBDocumentClient } from "@aws-sdk/lib-dynamodb"; import { ddbClient } from "./ddbClient.js"; const marshallOptions = { // Whether to automatically convert empty strings, blobs, and sets to `null`. convertEmptyValues: false, // false, by default. // Whether to remove undefined values while marshalling. removeUndefinedValues: false, // false, by default. // Whether to convert typeof object to map attribute. convertClassInstanceToMap: false, // false, by default. }; const unmarshallOptions = { // Whether to return numbers as a string instead of converting them to native JavaScript numbers. wrapNumbers: false, // false, by default. }; const translateConfig = { marshallOptions, unmarshallOptions }; // Create the DynamoDB document client. const ddbDocClient = DynamoDBDocumentClient.from(ddbClient, translateConfig); export { ddbDocClient };

Update an item in a table using the DynamoDB document client.

import { UpdateCommand } from "@aws-sdk/lib-dynamodb"; import { ddbDocClient } from "../libs/ddbDocClient.js"; export const updateItem = async () => { // Set the parameters. const params = { TableName: "TABLE_NAME", Key: { title: "MOVIE_NAME", year: "MOVIE_YEAR", }, ProjectionExpression: "#r", ExpressionAttributeNames: { "#r": "rank" }, UpdateExpression: "set info.plot = :p, info.#r = :r", ExpressionAttributeValues: { ":p": "MOVIE_PLOT", ":r": "MOVIE_RANK", }, }; try { const data = await ddbDocClient.send(new UpdateCommand(params)); console.log("Success - item added or updated", data); return data; } catch (err) { console.log("Error", err); } }; updateItem();

Update an item in a table using PartiQL.

// Import required AWS SDK clients and commands for Node.js. import { ExecuteStatementCommand } from "@aws-sdk/client-dynamodb"; import { ddbDocClient } from "../libs/ddbDocClient.js"; const tableName = process.argv[2]; const movieYear1 = process.argv[3]; const movieTitle1 = process.argv[4]; const producer1 = process.argv[5]; export const run = async (tableName, movieYear1, movieTitle1, producer1) => { const params = { Statement: "UPDATE " + tableName + " SET Producer=? where title=? and year=?", Parameters: [{ S: producer1 }, { S: movieTitle1 }, { N: movieYear1 }], }; try { await ddbDocClient.send(new ExecuteStatementCommand(params)); console.log("Success. Item updated."); return "Run successfully"; // For unit tests. } catch (err) { console.error(err); } }; run(tableName, movieYear1, movieTitle1, producer1);

Update items by batch in a table using PartiQL.

// Import required AWS SDK clients and commands for Node.js. import { BatchExecuteStatementCommand } from "@aws-sdk/client-dynamodb"; import { ddbDocClient } from "../libs/ddbDocClient.js"; const tableName = process.argv[2]; const movieYear1 = process.argv[3]; const movieTitle1 = process.argv[4]; const movieYear2 = process.argv[6]; const movieTitle2 = process.argv[7]; const producer1 = process.argv[5]; const producer2 = process.argv[8]; export const run = async ( tableName, movieYear1, movieTitle1, movieYear2, movieTitle2, producer1, producer2 ) => { const params = { Statements: [ { Statement: "UPDATE " + tableName + " SET producer=? where title=? and year=?", Parameters: [{ S: producer1 }, { S: movieTitle1 }, { N: movieYear1 }], }, { Statement: "UPDATE " + tableName + " SET producer=? where title=? and year=?", Parameters: [{ S: producer2 }, { S: movieTitle2 }, { N: movieYear2 }], }, ], }; try { await ddbDocClient.send( new BatchExecuteStatementCommand(params) ); console.log("Success. Items updated."); return "Run successfully"; // For unit tests. } catch (err) { console.error(err); } }; run( tableName, movieYear1, movieTitle1, movieYear2, movieTitle2, producer1, producer2 );
  • For API details, see UpdateItem in Amazon SDK for JavaScript API Reference.

Kotlin
SDK for Kotlin
Note

This is prerelease documentation for a feature in preview release. It is subject to change.

Note

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

suspend fun updateTableItem( tableNameVal: String, keyName: String, keyVal: String, name: String, updateVal: String ) { val itemKey = mutableMapOf<String, AttributeValue>() itemKey[keyName] = AttributeValue.S(keyVal) val updatedValues = mutableMapOf<String, AttributeValueUpdate>() updatedValues[name] = AttributeValueUpdate { value = AttributeValue.S(updateVal) action = AttributeAction.Put } val request = UpdateItemRequest { tableName = tableNameVal key = itemKey attributeUpdates = updatedValues } DynamoDbClient { region = "us-east-1" }.use { ddb -> ddb.updateItem(request) println("Item in $tableNameVal was updated") } }
  • For API details, see UpdateItem in Amazon SDK for Kotlin API reference.

PHP
SDK for PHP
Note

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

echo "What rating would you like to give {$movie['Item']['title']['S']}?\n"; $rating = 0; while (!is_numeric($rating) || intval($rating) != $rating || $rating < 1 || $rating > 10) { $rating = testable_readline("Rating (1-10): "); } $service->updateItemAttributeByKey($tableName, $key, 'rating', 'N', $rating); public function updateItemAttributeByKey( string $tableName, array $key, string $attributeName, string $attributeType, string $newValue ) { $this->dynamoDbClient->updateItem([ 'Key' => $key['Item'], 'TableName' => $tableName, 'UpdateExpression' => "set #NV=:NV", 'ExpressionAttributeNames' => [ '#NV' => $attributeName, ], 'ExpressionAttributeValues' => [ ':NV' => [ $attributeType => $newValue ] ], ]); }
  • For API details, see UpdateItem in Amazon SDK for PHP 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 Amazon Code Examples Repository.

Update an item by using an update expression.

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 self.table = None def update_movie(self, title, year, rating, plot): """ Updates rating and plot data for a movie in the table. :param title: The title of the movie to update. :param year: The release year of the movie to update. :param rating: The updated rating to the give the movie. :param plot: The updated plot summary to give the movie. :return: The fields that were updated, with their new values. """ try: response = self.table.update_item( Key={'year': year, 'title': title}, UpdateExpression="set info.rating=:r, info.plot=:p", ExpressionAttributeValues={ ':r': Decimal(str(rating)), ':p': plot}, ReturnValues="UPDATED_NEW") except ClientError as err: logger.error( "Couldn't update movie %s in table %s. Here's why: %s: %s", title, self.table.name, err.response['Error']['Code'], err.response['Error']['Message']) raise else: return response['Attributes']

Update an item by using an update expression that includes an arithmetic operation.

class UpdateQueryWrapper: def __init__(self, table): self.table = table def update_rating(self, title, year, rating_change): """ Updates the quality rating of a movie in the table by using an arithmetic operation in the update expression. By specifying an arithmetic operation, you can adjust a value in a single request, rather than first getting its value and then setting its new value. :param title: The title of the movie to update. :param year: The release year of the movie to update. :param rating_change: The amount to add to the current rating for the movie. :return: The updated rating. """ try: response = self.table.update_item( Key={'year': year, 'title': title}, UpdateExpression="set info.rating = info.rating + :val", ExpressionAttributeValues={':val': Decimal(str(rating_change))}, ReturnValues="UPDATED_NEW") except ClientError as err: logger.error( "Couldn't update movie %s in table %s. Here's why: %s: %s", title, self.table.name, err.response['Error']['Code'], err.response['Error']['Message']) raise else: return response['Attributes']

Update an item only when it meets certain conditions.

class UpdateQueryWrapper: def __init__(self, table): self.table = table def remove_actors(self, title, year, actor_threshold): """ Removes an actor from a movie, but only when the number of actors is greater than a specified threshold. If the movie does not list more than the threshold, no actors are removed. :param title: The title of the movie to update. :param year: The release year of the movie to update. :param actor_threshold: The threshold of actors to check. :return: The movie data after the update. """ try: response = self.table.update_item( Key={'year': year, 'title': title}, UpdateExpression="remove info.actors[0]", ConditionExpression="size(info.actors) > :num", ExpressionAttributeValues={':num': actor_threshold}, ReturnValues="ALL_NEW") except ClientError as err: if err.response['Error']['Code'] == "ConditionalCheckFailedException": logger.warning( "Didn't update %s because it has fewer than %s actors.", title, actor_threshold + 1) else: logger.error( "Couldn't update movie %s. Here's why: %s: %s", title, err.response['Error']['Code'], err.response['Error']['Message']) raise else: return response['Attributes']
  • For API details, see UpdateItem in Amazon 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 Amazon Code Examples Repository.

# Updates rating and plot data for a movie in the table. # # @param title [String] The title of the movie to update. # @param year [Int] The release year of the movie to update. # @param rating [Float] The updated rating to give the movie. # @param plot [String] The updated plot summary to give the movie. # @return [Hash] The fields that were updated, with their new values. def update_movie(title:, year:, rating:, plot:) response = @table.update_item( key: {"year" => year, "title" => title}, update_expression: "set info.rating=:r, info.plot=:p", expression_attribute_values: { ":r" => rating, ":p" => plot }, return_values: "UPDATED_NEW") rescue Aws::Errors::ServiceError => e puts("Couldn't update movie #{title} in table #{@table.name}. Here's why:") puts("\t#{e.code}: #{e.message}") raise else response.attributes end
  • For API details, see UpdateItem in Amazon SDK for Ruby API Reference.

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