使用 Amazon SDK 在 DynamoDB 表上运行批量 PartiQL 语句 - Amazon DynamoDB
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使用 Amazon SDK 在 DynamoDB 表上运行批量 PartiQL 语句

以下代码示例显示如何在 DynamoDB 表中运行批量 PartiQL 语句。

Go
SDK for Go V2
提示

要了解如何设置和运行此示例,请参阅 GitHub

使用批量 INSERT 语句添加项目。

// AddMovieBatch runs a batch of PartiQL INSERT statements to add multiple movies to the // DynamoDB table. func (runner PartiQLRunner) AddMovieBatch(movies []Movie) error { statementRequests := make([]types.BatchStatementRequest, len(movies)) for index, movie := range movies { params, err := attributevalue.MarshalList([]interface{}{movie.Title, movie.Year, movie.Info}) if err != nil { panic(err) } statementRequests[index] = types.BatchStatementRequest{ Statement: aws.String(fmt.Sprintf( "INSERT INTO \"%v\" VALUE {'title': ?, 'year': ?, 'info': ?}", runner.TableName)), Parameters: params, } } _, err := runner.DynamoDbClient.BatchExecuteStatement(context.TODO(), &dynamodb.BatchExecuteStatementInput{ Statements: statementRequests, }) if err != nil { log.Printf("Couldn't insert a batch of items with PartiQL. Here's why: %v\n", err) } return err }

使用批量 SELECT 语句获取项目。

// GetMovieBatch runs a batch of PartiQL SELECT statements to get multiple movies from // the DynamoDB table by title and year. func (runner PartiQLRunner) GetMovieBatch(movies []Movie) ([]Movie, error) { statementRequests := make([]types.BatchStatementRequest, len(movies)) for index, movie := range movies { params, err := attributevalue.MarshalList([]interface{}{movie.Title, movie.Year}) if err != nil { panic(err) } statementRequests[index] = types.BatchStatementRequest{ Statement: aws.String( fmt.Sprintf("SELECT * FROM \"%v\" WHERE title=? AND year=?", runner.TableName)), Parameters: params, } } output, err := runner.DynamoDbClient.BatchExecuteStatement(context.TODO(), &dynamodb.BatchExecuteStatementInput{ Statements: statementRequests, }) var outMovies []Movie if err != nil { log.Printf("Couldn't get a batch of items with PartiQL. Here's why: %v\n", err) } else { for _, response := range output.Responses { var movie Movie err = attributevalue.UnmarshalMap(response.Item, &movie) if err != nil { log.Printf("Couldn't unmarshal response. Here's why: %v\n", err) } else { outMovies = append(outMovies, movie) } } } return outMovies, err }

使用批量 UPDATE 语句更新项目。

// UpdateMovieBatch runs a batch of PartiQL UPDATE statements to update the rating of // multiple movies that already exist in the DynamoDB table. func (runner PartiQLRunner) UpdateMovieBatch(movies []Movie, ratings []float64) error { statementRequests := make([]types.BatchStatementRequest, len(movies)) for index, movie := range movies { params, err := attributevalue.MarshalList([]interface{}{ratings[index], movie.Title, movie.Year}) if err != nil { panic(err) } statementRequests[index] = types.BatchStatementRequest{ Statement: aws.String( fmt.Sprintf("UPDATE \"%v\" SET info.rating=? WHERE title=? AND year=?", runner.TableName)), Parameters: params, } } _, err := runner.DynamoDbClient.BatchExecuteStatement(context.TODO(), &dynamodb.BatchExecuteStatementInput{ Statements: statementRequests, }) if err != nil { log.Printf("Couldn't update the batch of movies. Here's why: %v\n", err) } return err }

使用批量 DELETE 语句删除项目。

// DeleteMovieBatch runs a batch of PartiQL DELETE statements to remove multiple movies // from the DynamoDB table. func (runner PartiQLRunner) DeleteMovieBatch(movies []Movie) error { statementRequests := make([]types.BatchStatementRequest, len(movies)) for index, movie := range movies { params, err := attributevalue.MarshalList([]interface{}{movie.Title, movie.Year}) if err != nil { panic(err) } statementRequests[index] = types.BatchStatementRequest{ Statement: aws.String( fmt.Sprintf("DELETE FROM \"%v\" WHERE title=? AND year=?", runner.TableName)), Parameters: params, } } _, err := runner.DynamoDbClient.BatchExecuteStatement(context.TODO(), &dynamodb.BatchExecuteStatementInput{ Statements: statementRequests, }) if err != nil { log.Printf("Couldn't delete the batch of movies. Here's why: %v\n", err) } return err }
JavaScript
SDK for JavaScript V3
提示

要了解如何设置和运行此示例,请参阅 GitHub

创建客户端。

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

创建 DynamoDB 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"; // Set the AWS Region. const REGION = "eu-west-1"; // For example, "us-east-1". 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 };

使用 PartiQL 创建一批项目。

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

使用 PartiQL 获取一批项目。

// 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 ) => { const params = { Statements: [ { Statement: "SELECT * FROM " + tableName + " where title=? and year=?", Parameters: [{ S: movieTitle1 }, { N: movieYear1 }], }, { Statement: "SELECT * FROM " + tableName + " where title=? and year=?", Parameters: [{ S: movieTitle2 }, { N: movieYear2 }], }, ], }; try { const data = await ddbDocClient.send( new BatchExecuteStatementCommand(params) ); for (let i = 0; i < data.Responses.length; i++) { console.log(data.Responses[i].Item.year); console.log(data.Responses[i].Item.title); } return "Run successfully"; // For unit tests. } catch (err) { console.error(err); } }; run(tableName, movieYear1, movieTitle1, movieYear2, movieTitle2);

使用 PartiQL 更新一批项目。

// 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[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 { const data = 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 );

使用 PartiQL 删除一批项目。

// 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);
  • 有关 API 详细信息,请参阅《Amazon SDK for JavaScript API 参考》中的 BatchExecuteStatement

Python
适用于 Python (Boto3) 的 SDK
提示

要了解如何设置和运行此示例,请参阅 GitHub

class PartiQLBatchWrapper: """ Encapsulates a DynamoDB resource to run PartiQL statements. """ def __init__(self, dyn_resource): """ :param dyn_resource: A Boto3 DynamoDB resource. """ self.dyn_resource = dyn_resource def run_partiql(self, statements, param_list): """ Runs a PartiQL statement. A Boto3 resource is used even though `execute_statement` is called on the underlying `client` object because the resource transforms input and output from plain old Python objects (POPOs) to the DynamoDB format. If you create the client directly, you must do these transforms yourself. :param statements: The batch of PartiQL statements. :param param_list: The batch of PartiQL parameters that are associated with each statement. This list must be in the same order as the statements. :return: The responses returned from running the statements, if any. """ try: output = self.dyn_resource.meta.client.batch_execute_statement( Statements=[{ 'Statement': statement, 'Parameters': params } for statement, params in zip(statements, param_list)]) except ClientError as err: if err.response['Error']['Code'] == 'ResourceNotFoundException': logger.error( "Couldn't execute batch of PartiQL statements because the table " "does not exist.") else: logger.error( "Couldn't execute batch of PartiQL statements. Here's why: %s: %s", err.response['Error']['Code'], err.response['Error']['Message']) raise else: return output
  • 有关 API 详细信息,请参阅《适用于 Python (Boto3) 的 Amazon SDK API 参考》中的 BatchExecuteStatement

有关 Amazon 软件开发工具包开发人员指南和代码示例的完整列表,请参阅 结合使用 DynamoDB 与 Amazon SDK。本主题还包括有关入门的信息以及有关先前的软件开发工具包版本的详细信息。