使用 Java SDK v2 在 DynamoDB 中高效批量删除数据

import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbBean;
import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbPartitionKey;
import software.amazon.awssdk.enhanced.dynamodb.mapper.annotations.DynamoDbSortKey;

@DynamoDbBean
public class MyItem {
    private String partitionKey;
    private String sortKey;
    private String data; // 其他属性

    @DynamoDbPartitionKey
    public String getPartitionKey() {
        return partitionKey;
    }

    public void setPartitionKey(String partitionKey) {
        this.partitionKey = partitionKey;
    }

    @DynamoDbSortKey // 如果有排序键
    public String getSortKey() {
        return sortKey;
    }

    public void setSortKey(String sortKey) {
        this.sortKey = sortKey;
    }

    public String getData() {
        return data;
    }

    public void setData(String data) {
        this.data = data;
    }

    // 构造函数，用于方便创建待删除项（只需要主键）
    public MyItem(String partitionKey, String sortKey) {
        this.partitionKey = partitionKey;
        this.sortKey = sortKey;
    }

    public MyItem() {} // 默认构造函数是必须的
}

import software.amazon.awssdk.enhanced.dynamodb.DynamoDbEnhancedClient;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.dynamodb.DynamoDbClient;

public class DynamoDBBatchDeleter {

    private final DynamoDbEnhancedClient enhancedClient;
    private final String tableName;

    public DynamoDBBatchDeleter(String tableName) {
        this.tableName = tableName;
        DynamoDbClient ddb = DynamoDbClient.builder()
                .region(Region.AP_SOUTHEAST_1) // 根据您的实际情况选择区域
                .build();
        this.enhancedClient = DynamoDbEnhancedClient.builder()
                .dynamoDbClient(ddb)
                .build();
    }

    // ... 批量删除方法将在这里实现
}

import software.amazon.awssdk.enhanced.dynamodb.model.BatchWriteItemEnhancedRequest;
import software.amazon.awssdk.enhanced.dynamodb.model.WriteBatch;
import software.amazon.awssdk.services.dynamodb.model.BatchWriteItemResponse;
import java.util.List;
import java.util.Map;

// 假设您已经有 DynamoDBBatchDeleter 类和 MyItem 实体类

public class DynamoDBBatchDeleter {
    // ... 构造函数和客户端初始化

    public void batchDeleteItems(List<MyItem> itemsToDelete) {
        if (itemsToDelete == null || itemsToDelete.isEmpty()) {
            System.out.println("没有要删除的项。");
            return;
        }

        BatchWriteItemEnhancedRequest.Builder batchBuilder = BatchWriteItemEnhancedRequest.builder();

        // 将每个待删除项添加到批量请求中
        itemsToDelete.forEach(item ->
                batchBuilder.addWriteBatch(
                        WriteBatch.builder(MyItem.class) // 指定实体类
                                .addDeleteItem(item) // 添加删除操作，传入包含主键的MyItem对象
                                .build()
                )
        );

        System.out.println("尝试批量删除 " + itemsToDelete.size() + " 个项。");
        BatchWriteItemResponse response = enhancedClient.batchWriteItem(batchBuilder.build());

        // 处理未处理的项
        if (response.hasUnprocessedItems() && !response.unprocessedItems().isEmpty()) {
            System.out.println("部分项未能成功处理。您可能需要重试这些项。");
            for (Map.Entry<String, software.amazon.awssdk.services.dynamodb.model.WriteRequest> entry : response.unprocessedItems().entrySet()) {
                System.out.println("表名: " + entry.getKey() + ", 未处理请求: " + entry.getValue());
            }
            // 在实际应用中，您应该将这些未处理的请求重新放入队列进行重试
        } else {
            System.out.println("所有项已成功批量删除。");
        }
    }

    public static void main(String[] args) {
        String tableName = "YourActualTableName"; // 替换为您的 DynamoDB 表名
        DynamoDBBatchDeleter deleter = new DynamoDBBatchDeleter(tableName);

        // 示例：创建要删除的项列表 (只需要主键信息)
        List<MyItem> itemsToDelete = new java.util.ArrayList<>();
        itemsToDelete.add(new MyItem("user#123", "order#A001"));
        itemsToDelete.add(new MyItem("user#123", "order#A002"));
        itemsToDelete.add(new MyItem("user#456", "profile"));
        // ... 添加更多项，但请注意单个批次请求的限制

        deleter.batchDeleteItems(itemsToDelete);
    }
}