使用 Amazon SDK 通过 PartiQL DELETE 语句删除 DynamoDB 数据

使用适用于 JavaScript 的 Amazon SDK 通过 PartiQL DELETE 语句从 DynamoDB 表中删除项目。

/**
 * This example demonstrates how to delete items from a DynamoDB table using PartiQL.
 * It shows different ways to delete documents with various index types.
 */
import { DynamoDBClient } from "@aws-sdk/client-dynamodb";
import {
  DynamoDBDocumentClient,
  ExecuteStatementCommand,
  BatchExecuteStatementCommand,
} from "@aws-sdk/lib-dynamodb";

/**
 * Delete a single item by its partition key using PartiQL.
 * 
 * @param tableName - The name of the DynamoDB table
 * @param partitionKeyName - The name of the partition key attribute
 * @param partitionKeyValue - The value of the partition key
 * @returns The response from the ExecuteStatementCommand
 */
export const deleteItemByPartitionKey = async (
  tableName: string,
  partitionKeyName: string,
  partitionKeyValue: string | number
) => {
  const client = new DynamoDBClient({});
  const docClient = DynamoDBDocumentClient.from(client);

  const params = {
    Statement: `DELETE FROM "${tableName}" WHERE ${partitionKeyName} = ?`,
    Parameters: [partitionKeyValue],
  };

  try {
    const data = await docClient.send(new ExecuteStatementCommand(params));
    console.log("Item deleted successfully");
    return data;
  } catch (err) {
    console.error("Error deleting item:", err);
    throw err;
  }
};

/**
 * Delete an item by its composite key (partition key + sort key) using PartiQL.
 * 
 * @param tableName - The name of the DynamoDB table
 * @param partitionKeyName - The name of the partition key attribute
 * @param partitionKeyValue - The value of the partition key
 * @param sortKeyName - The name of the sort key attribute
 * @param sortKeyValue - The value of the sort key
 * @returns The response from the ExecuteStatementCommand
 */
export const deleteItemByCompositeKey = async (
  tableName: string,
  partitionKeyName: string,
  partitionKeyValue: string | number,
  sortKeyName: string,
  sortKeyValue: string | number
) => {
  const client = new DynamoDBClient({});
  const docClient = DynamoDBDocumentClient.from(client);

  const params = {
    Statement: `DELETE FROM "${tableName}" WHERE ${partitionKeyName} = ? AND ${sortKeyName} = ?`,
    Parameters: [partitionKeyValue, sortKeyValue],
  };

  try {
    const data = await docClient.send(new ExecuteStatementCommand(params));
    console.log("Item deleted successfully");
    return data;
  } catch (err) {
    console.error("Error deleting item:", err);
    throw err;
  }
};

/**
 * Delete an item with a condition to ensure the delete only happens if a condition is met.
 * 
 * @param tableName - The name of the DynamoDB table
 * @param partitionKeyName - The name of the partition key attribute
 * @param partitionKeyValue - The value of the partition key
 * @param conditionAttribute - The attribute to check in the condition
 * @param conditionValue - The value to compare against in the condition
 * @returns The response from the ExecuteStatementCommand
 */
export const deleteItemWithCondition = async (
  tableName: string,
  partitionKeyName: string,
  partitionKeyValue: string | number,
  conditionAttribute: string,
  conditionValue: any
) => {
  const client = new DynamoDBClient({});
  const docClient = DynamoDBDocumentClient.from(client);

  const params = {
    Statement: `DELETE FROM "${tableName}" WHERE ${partitionKeyName} = ? AND ${conditionAttribute} = ?`,
    Parameters: [partitionKeyValue, conditionValue],
  };

  try {
    const data = await docClient.send(new ExecuteStatementCommand(params));
    console.log("Item deleted with condition successfully");
    return data;
  } catch (err) {
    console.error("Error deleting item with condition:", err);
    throw err;
  }
};

/**
 * Batch delete multiple items using PartiQL.
 * 
 * @param tableName - The name of the DynamoDB table
 * @param keys - Array of objects containing key information
 * @returns The response from the BatchExecuteStatementCommand
 */
export const batchDeleteItems = async (
  tableName: string,
  keys: Array<{
    partitionKeyName: string;
    partitionKeyValue: string | number;
    sortKeyName?: string;
    sortKeyValue?: string | number;
  }>
) => {
  const client = new DynamoDBClient({});
  const docClient = DynamoDBDocumentClient.from(client);

  // Create statements for each delete
  const statements = keys.map((key) => {
    if (key.sortKeyName && key.sortKeyValue !== undefined) {
      return {
        Statement: `DELETE FROM "${tableName}" WHERE ${key.partitionKeyName} = ? AND ${key.sortKeyName} = ?`,
        Parameters: [key.partitionKeyValue, key.sortKeyValue],
      };
    } else {
      return {
        Statement: `DELETE FROM "${tableName}" WHERE ${key.partitionKeyName} = ?`,
        Parameters: [key.partitionKeyValue],
      };
    }
  });

  const params = {
    Statements: statements,
  };

  try {
    const data = await docClient.send(new BatchExecuteStatementCommand(params));
    console.log("Items batch deleted successfully");
    return data;
  } catch (err) {
    console.error("Error batch deleting items:", err);
    throw err;
  }
};

/**
 * Delete multiple items that match a filter condition.
 * Note: This performs a scan operation which can be expensive on large tables.
 * 
 * @param tableName - The name of the DynamoDB table
 * @param filterAttribute - The attribute to filter on
 * @param filterValue - The value to filter by
 * @returns The response from the ExecuteStatementCommand
 */
export const deleteItemsByFilter = async (
  tableName: string,
  filterAttribute: string,
  filterValue: any
) => {
  const client = new DynamoDBClient({});
  const docClient = DynamoDBDocumentClient.from(client);

  const params = {
    Statement: `DELETE FROM "${tableName}" WHERE ${filterAttribute} = ?`,
    Parameters: [filterValue],
  };

  try {
    const data = await docClient.send(new ExecuteStatementCommand(params));
    console.log("Items deleted by filter successfully");
    return data;
  } catch (err) {
    console.error("Error deleting items by filter:", err);
    throw err;
  }
};

/**
 * Example usage showing how to delete items with different index types
 */
export const deleteExamples = async () => {
  // Delete an item by partition key (simple primary key)
  await deleteItemByPartitionKey("UsersTable", "userId", "user123");

  // Delete an item by composite key (partition key + sort key)
  await deleteItemByCompositeKey(
    "OrdersTable",
    "orderId",
    "order456",
    "productId",
    "prod789"
  );

  // Delete with a condition
  await deleteItemWithCondition(
    "UsersTable",
    "userId",
    "user789",
    "userStatus",
    "inactive"
  );

  // Batch delete multiple items
  await batchDeleteItems("UsersTable", [
    { partitionKeyName: "userId", partitionKeyValue: "user234" },
    { partitionKeyName: "userId", partitionKeyValue: "user345" },
  ]);

  // Batch delete items with composite keys
  await batchDeleteItems("OrdersTable", [
    {
      partitionKeyName: "orderId",
      partitionKeyValue: "order567",
      sortKeyName: "productId",
      sortKeyValue: "prod123",
    },
    {
      partitionKeyName: "orderId",
      partitionKeyValue: "order678",
      sortKeyName: "productId",
      sortKeyValue: "prod456",
    },
  ]);

  // Delete items by filter (use with caution)
  await deleteItemsByFilter("UsersTable", "userStatus", "deleted");
};