使用 Amazon SDK 删除 DynamoDB 表中的项目

        /// <summary>
        /// Deletes a single item from a DynamoDB table.
        /// </summary>
        /// <param name="client">The initialized DynamoDB client object.</param>
        /// <param name="tableName">The name of the table from which the item
        /// will be deleted.</param>
        /// <param name="movieToDelete">A movie object containing the title and
        /// year of the movie to delete.</param>
        /// <returns>A Boolean value indicating the success or failure of the
        /// delete operation.</returns>
        public static async Task<bool> DeleteItemAsync(
            AmazonDynamoDBClient client,
            string tableName,
            Movie movieToDelete)
        {
            var key = new Dictionary<string, AttributeValue>
            {
                ["title"] = new AttributeValue { S = movieToDelete.Title },
                ["year"] = new AttributeValue { N = movieToDelete.Year.ToString() },
            };

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

            var response = await client.DeleteItemAsync(request);
            return response.HttpStatusCode == System.Net.HttpStatusCode.OK;
        }

//! Delete an item from an Amazon DynamoDB table.
/*!
  \sa deleteItem()
  \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::deleteItem(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::DeleteItemRequest request;

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

    const Aws::DynamoDB::Model::DeleteItemOutcome &outcome = dynamoClient.DeleteItem(
            request);
    if (outcome.IsSuccess()) {
        std::cout << "Item \"" << partitionValue << "\" deleted!" << std::endl;
    }
    else {
        std::cerr << "Failed to delete item: " << outcome.GetError().GetMessage()
                  << std::endl;
    }

    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
}



// DeleteMovie removes a movie from the DynamoDB table.
func (basics TableBasics) DeleteMovie(movie Movie) error {
	_, err := basics.DynamoDbClient.DeleteItem(context.TODO(), &dynamodb.DeleteItemInput{
		TableName: aws.String(basics.TableName), Key: movie.GetKey(),
	})
	if err != nil {
		log.Printf("Couldn't delete %v from the table. Here's why: %v\n", movie.Title, err)
	}
	return err
}

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

        DeleteItemRequest deleteReq = DeleteItemRequest.builder()
            .tableName(tableName)
            .key(keyToGet)
            .build();

        try {
            ddb.deleteItem(deleteReq);
        } catch (DynamoDbException e) {
           System.err.println(e.getMessage());
           System.exit(1);
        }
    }

创建客户端。

// Create the DynamoDB service client module using ES6 syntax.
import { DynamoDBClient } from "@aws-sdk/client-dynamodb";
import { DEFAULT_REGION } from "../../../../libs/utils/util-aws-sdk.js";
// Create an Amazon DynamoDB service client object.
export const ddbClient = new DynamoDBClient({ region: DEFAULT_REGION });

创建文档客户端。

// 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: true, // 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.
};

// Create the DynamoDB document client.
const ddbDocClient = DynamoDBDocumentClient.from(ddbClient, {
  marshallOptions,
  unmarshallOptions,
});

export { ddbDocClient };

使用 DynamoDB 文档客户端从表中删除项目。

import { DeleteCommand } from "@aws-sdk/lib-dynamodb";
import { ddbDocClient } from "../libs/ddbDocClient.js";

// Set the parameters.
export const params = {
  TableName: "TABLE_NAME",
  Key: {
    primaryKey: "VALUE_1",
    sortKey: "VALUE_2",
  },
};

export const deleteItem = async () => {
  try {
    await ddbDocClient.send(new DeleteCommand(params));
    console.log("Success - item deleted");
  } catch (err) {
    console.log("Error", err);
  }
};
deleteItem();

使用 PartiQL 从表中删除项目。

// 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];

export const run = async (tableName, movieYear1, movieTitle1) => {
  const params = {
    Statement: "DELETE FROM " + tableName + " where title=? and year=?",
    Parameters: [{ S: movieTitle1 }, { N: movieYear1 }],
  };
  try {
    await ddbDocClient.send(new ExecuteStatementCommand(params));
    console.log("Success. Item deleted.");
    return "Run successfully"; // For unit tests.
  } catch (err) {
    console.error(err);
  }
};
run(tableName, movieYear1, movieTitle1);

使用 PartiQL 批量删除表中的项目。

// 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[5];
const movieTitle2 = process.argv[6];

export const run = async (
  tableName,
  movieYear1,
  movieTitle1,
  movieYear2,
  movieTitle2
) => {
  try {
    const params = {
      Statements: [
        {
          Statement: "DELETE FROM " + tableName + "  where year=? and title=?",
          Parameters: [{ N: movieYear1 }, { S: movieTitle1 }],
        },
        {
          Statement: "DELETE FROM " + tableName + "  where year=? and title=?",
          Parameters: [{ N: movieYear2 }, { S: movieTitle2 }],
        },
      ],
    };
    const data = await ddbDocClient.send(
      new BatchExecuteStatementCommand(params)
    );
    console.log("Success. Items deleted.", data);
    return "Run successfully"; // For unit tests.
  } catch (err) {
    console.error(err);
  }
};
run(tableName, movieYear1, movieTitle1, movieYear2, movieTitle2);

从表中删除项目。

// 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: 'VALUE'}
  }
};

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

使用 DynamoDB 文档客户端从表中删除项目。

// 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 = {
  Key: {
    'HASH_KEY': VALUE
  },
  TableName: 'TABLE'
};

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

suspend fun deleteDynamoDBItem(tableNameVal: String, keyName: String, keyVal: String) {
    val keyToGet = mutableMapOf<String, AttributeValue>()
    keyToGet[keyName] = AttributeValue.S(keyVal)

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

    DynamoDbClient { region = "us-east-1" }.use { ddb ->
        ddb.deleteItem(request)
        println("Item with key matching $keyVal was deleted")
    }
}

        $key = [
            'Item' => [
                'title' => [
                    'S' => $movieName,
                ],
                'year' => [
                    'N' => $movieYear,
                ],
            ]
        ];

        $service->deleteItemByKey($tableName, $key);
        echo "But, bad news, this was a trap. That movie has now been deleted because of your rating...harsh.\n";

    public function deleteItemByKey(string $tableName, array $key)
    {
        $this->dynamoDbClient->deleteItem([
            '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
        self.table = None

    def delete_movie(self, title, year):
        """
        Deletes a movie from the table.

        :param title: The title of the movie to delete.
        :param year: The release year of the movie to delete.
        """
        try:
            self.table.delete_item(Key={'year': year, 'title': title})
        except ClientError as err:
            logger.error(
                "Couldn't delete movie %s. Here's why: %s: %s", title,
                err.response['Error']['Code'], err.response['Error']['Message'])
            raise

您可以指定条件，以便只有在项目满足特定条件时才会被删除。

class UpdateQueryWrapper:
    def __init__(self, table):
        self.table = table

    def delete_underrated_movie(self, title, year, rating):
        """
        Deletes a movie only if it is rated below a specified value. By using a
        condition expression in a delete operation, you can specify that an item is
        deleted only when it meets certain criteria.

        :param title: The title of the movie to delete.
        :param year: The release year of the movie to delete.
        :param rating: The rating threshold to check before deleting the movie.
        """
        try:
            self.table.delete_item(
                Key={'year': year, 'title': title},
                ConditionExpression="info.rating <= :val",
                ExpressionAttributeValues={":val": Decimal(str(rating))})
        except ClientError as err:
            if err.response['Error']['Code'] == "ConditionalCheckFailedException":
                logger.warning(
                    "Didn't delete %s because its rating is greater than %s.",
                    title, rating)
            else:
                logger.error(
                    "Couldn't delete movie %s. Here's why: %s: %s", title,
                    err.response['Error']['Code'], err.response['Error']['Message'])
            raise

  # Deletes a movie from the table.
  #
  # @param title [String] The title of the movie to delete.
  # @param year [Integer] The release year of the movie to delete.
  def delete_movie(title, year)
    @table.delete_item(key: {"year" => year, "title" => title})
  rescue Aws::Errors::ServiceError => e
    puts("Couldn't delete movie #{title}. Here's why:")
    puts("\t#{e.code}: #{e.message}")
    raise
  end

pub async fn delete_item(
    client: &Client,
    table: &str,
    key: &str,
    value: &str,
) -> Result<DeleteItemOutput, Error> {
    match client
        .delete_item()
        .table_name(table)
        .key(key, AttributeValue::S(value.into()))
        .send()
        .await
    {
        Ok(out) => {
            println!("Deleted item from table");
            Ok(out)
        }
        Err(e) => Err(Error::unhandled(e)),
    }
}