예: Java 문서 API를 사용하는 로컬 보조 인덱스 - Amazon DynamoDB

예: Java 문서 API를 사용하는 로컬 보조 인덱스

다음 Java 코드 예제는 Amazon DynamoDB에서 로컬 보조 인덱스로 작업하는 방법을 보여 줍니다. 예를 들어 파티션 키가 CustomerOrders이고 정렬 키가 CustomerId인 OrderId라는 테이블을 만들 수 있습니다. 이 테이블에는 두 개의 로컬 보조 인덱스가 있습니다.

  • OrderCreationDateIndex - 정렬 키는 OrderCreationDate이며 다음 속성이 인덱스로 프로젝션됩니다.

    • ProductCategory

    • ProductName

    • OrderStatus

    • ShipmentTrackingId

  • IsOpenIndex - 정렬 키는 IsOpen이며 모든 테이블 속성이 인덱스로 프로젝션됩니다.

CustomerOrders 테이블이 생성되면 프로그램에서 고객 주문을 나타내는 데이터와 함께 테이블을 로드합니다. 그런 다음 로컬 보조 인덱스를 사용하여 데이터를 쿼리합니다. 마지막으로 프로그램에서 CustomerOrders 테이블을 삭제합니다.

다음 샘플을 테스트하기 위한 단계별 지침은 Java 코드 예 섹션을 참조하세요.

예 

package com.example.dynamodb;

import software.amazon.awssdk.core.waiters.WaiterResponse;
import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
import software.amazon.awssdk.services.dynamodb.model.*;
import software.amazon.awssdk.services.dynamodb.waiters.DynamoDbWaiter;

import java.util.HashMap;
import java.util.Map;

public class DocumentAPILocalSecondaryIndexExample {

    static DynamoDbClient client = DynamoDbClient.create();
    public static String tableName = "CustomerOrders";

    public static void main(String[] args) {
        createTable();
        loadData();
        query(null);
        query("IsOpenIndex");
        query("OrderCreationDateIndex");
        deleteTable(tableName);
    }

    public static void createTable() {
        CreateTableRequest request = CreateTableRequest.builder()
            .tableName(tableName)
            .provisionedThroughput(ProvisionedThroughput.builder()
                .readCapacityUnits(1L)
                .writeCapacityUnits(1L)
                .build())
            .attributeDefinitions(
                AttributeDefinition.builder().attributeName("CustomerId").attributeType(ScalarAttributeType.S).build(),
                AttributeDefinition.builder().attributeName("OrderId").attributeType(ScalarAttributeType.N).build(),
                AttributeDefinition.builder().attributeName("OrderCreationDate").attributeType(ScalarAttributeType.N).build(),
                AttributeDefinition.builder().attributeName("IsOpen").attributeType(ScalarAttributeType.N).build())
            .keySchema(
                KeySchemaElement.builder().attributeName("CustomerId").keyType(KeyType.HASH).build(),
                KeySchemaElement.builder().attributeName("OrderId").keyType(KeyType.RANGE).build())
            .localSecondaryIndexes(
                LocalSecondaryIndex.builder()
                    .indexName("OrderCreationDateIndex")
                    .keySchema(
                        KeySchemaElement.builder().attributeName("CustomerId").keyType(KeyType.HASH).build(),
                        KeySchemaElement.builder().attributeName("OrderCreationDate").keyType(KeyType.RANGE).build())
                    .projection(Projection.builder()
                        .projectionType(ProjectionType.INCLUDE)
                        .nonKeyAttributes("ProductCategory", "ProductName")
                        .build())
                    .build(),
                LocalSecondaryIndex.builder()
                    .indexName("IsOpenIndex")
                    .keySchema(
                        KeySchemaElement.builder().attributeName("CustomerId").keyType(KeyType.HASH).build(),
                        KeySchemaElement.builder().attributeName("IsOpen").keyType(KeyType.RANGE).build())
                    .projection(Projection.builder()
                        .projectionType(ProjectionType.ALL)
                        .build())
                    .build())
            .build();

        System.out.println("Creating table " + tableName + "...");
        client.createTable(request);

        try (DynamoDbWaiter waiter = client.waiter()) {
            WaiterResponse<DescribeTableResponse> response = waiter.waitUntilTableExists(r -> r.tableName(tableName));
            response.matched().response().ifPresent(System.out::println);
        }
    }

    public static void query(String indexName) {
        System.out.println("\n***********************************************************\n");
        System.out.println("Querying table " + tableName + "...");

        if ("IsOpenIndex".equals(indexName)) {
            System.out.println("\nUsing index: '" + indexName + "': Bob's orders that are open.");
            System.out.println("Only a user-specified list of attributes are returned\n");

            Map<String, AttributeValue> values = new HashMap<>();
            values.put(":v_custid", AttributeValue.builder().s("bob@example.com").build());
            values.put(":v_isopen", AttributeValue.builder().n("1").build());

            QueryRequest request = QueryRequest.builder()
                .tableName(tableName)
                .indexName(indexName)
                .keyConditionExpression("CustomerId = :v_custid and IsOpen = :v_isopen")
                .expressionAttributeValues(values)
                .projectionExpression("OrderCreationDate, ProductCategory, ProductName, OrderStatus")
                .build();

            System.out.println("Query: printing results...");
            client.query(request).items().forEach(System.out::println);

        } else if ("OrderCreationDateIndex".equals(indexName)) {
            System.out.println("\nUsing index: '" + indexName + "': Bob's orders that were placed after 01/31/2015.");
            System.out.println("Only the projected attributes are returned\n");

            Map<String, AttributeValue> values = new HashMap<>();
            values.put(":v_custid", AttributeValue.builder().s("bob@example.com").build());
            values.put(":v_orddate", AttributeValue.builder().n("20150131").build());

            QueryRequest request = QueryRequest.builder()
                .tableName(tableName)
                .indexName(indexName)
                .keyConditionExpression("CustomerId = :v_custid and OrderCreationDate >= :v_orddate")
                .expressionAttributeValues(values)
                .select(Select.ALL_PROJECTED_ATTRIBUTES)
                .build();

            System.out.println("Query: printing results...");
            client.query(request).items().forEach(System.out::println);

        } else {
            System.out.println("\nNo index: All of Bob's orders, by OrderId:\n");

            Map<String, AttributeValue> values = new HashMap<>();
            values.put(":v_custid", AttributeValue.builder().s("bob@example.com").build());

            QueryRequest request = QueryRequest.builder()
                .tableName(tableName)
                .keyConditionExpression("CustomerId = :v_custid")
                .expressionAttributeValues(values)
                .build();

            System.out.println("Query: printing results...");
            client.query(request).items().forEach(System.out::println);
        }
    }

    public static void deleteTable(String tableName) {
        System.out.println("Deleting table " + tableName + "...");
        client.deleteTable(DeleteTableRequest.builder().tableName(tableName).build());

        try (DynamoDbWaiter waiter = client.waiter()) {
            waiter.waitUntilTableNotExists(r -> r.tableName(tableName));
        }
    }

    public static void loadData() {
        System.out.println("Loading data into table " + tableName + "...");

        putItem(Map.of(
            "CustomerId", AttributeValue.builder().s("alice@example.com").build(),
            "OrderId", AttributeValue.builder().n("1").build(),
            "IsOpen", AttributeValue.builder().n("1").build(),
            "OrderCreationDate", AttributeValue.builder().n("20150101").build(),
            "ProductCategory", AttributeValue.builder().s("Book").build(),
            "ProductName", AttributeValue.builder().s("The Great Outdoors").build(),
            "OrderStatus", AttributeValue.builder().s("PACKING ITEMS").build()));

        putItem(Map.of(
            "CustomerId", AttributeValue.builder().s("alice@example.com").build(),
            "OrderId", AttributeValue.builder().n("2").build(),
            "IsOpen", AttributeValue.builder().n("1").build(),
            "OrderCreationDate", AttributeValue.builder().n("20150221").build(),
            "ProductCategory", AttributeValue.builder().s("Bike").build(),
            "ProductName", AttributeValue.builder().s("Super Mountain").build(),
            "OrderStatus", AttributeValue.builder().s("ORDER RECEIVED").build()));

        putItem(Map.of(
            "CustomerId", AttributeValue.builder().s("alice@example.com").build(),
            "OrderId", AttributeValue.builder().n("3").build(),
            "OrderCreationDate", AttributeValue.builder().n("20150304").build(),
            "ProductCategory", AttributeValue.builder().s("Music").build(),
            "ProductName", AttributeValue.builder().s("A Quiet Interlude").build(),
            "OrderStatus", AttributeValue.builder().s("IN TRANSIT").build(),
            "ShipmentTrackingId", AttributeValue.builder().s("176493").build()));

        putItem(Map.of(
            "CustomerId", AttributeValue.builder().s("bob@example.com").build(),
            "OrderId", AttributeValue.builder().n("1").build(),
            "OrderCreationDate", AttributeValue.builder().n("20150111").build(),
            "ProductCategory", AttributeValue.builder().s("Movie").build(),
            "ProductName", AttributeValue.builder().s("Calm Before The Storm").build(),
            "OrderStatus", AttributeValue.builder().s("SHIPPING DELAY").build(),
            "ShipmentTrackingId", AttributeValue.builder().s("859323").build()));

        putItem(Map.of(
            "CustomerId", AttributeValue.builder().s("bob@example.com").build(),
            "OrderId", AttributeValue.builder().n("2").build(),
            "OrderCreationDate", AttributeValue.builder().n("20150124").build(),
            "ProductCategory", AttributeValue.builder().s("Music").build(),
            "ProductName", AttributeValue.builder().s("E-Z Listening").build(),
            "OrderStatus", AttributeValue.builder().s("DELIVERED").build(),
            "ShipmentTrackingId", AttributeValue.builder().s("756943").build()));

        putItem(Map.of(
            "CustomerId", AttributeValue.builder().s("bob@example.com").build(),
            "OrderId", AttributeValue.builder().n("3").build(),
            "OrderCreationDate", AttributeValue.builder().n("20150221").build(),
            "ProductCategory", AttributeValue.builder().s("Music").build(),
            "ProductName", AttributeValue.builder().s("Symphony 9").build(),
            "OrderStatus", AttributeValue.builder().s("DELIVERED").build(),
            "ShipmentTrackingId", AttributeValue.builder().s("645193").build()));

        putItem(Map.of(
            "CustomerId", AttributeValue.builder().s("bob@example.com").build(),
            "OrderId", AttributeValue.builder().n("4").build(),
            "IsOpen", AttributeValue.builder().n("1").build(),
            "OrderCreationDate", AttributeValue.builder().n("20150222").build(),
            "ProductCategory", AttributeValue.builder().s("Hardware").build(),
            "ProductName", AttributeValue.builder().s("Extra Heavy Hammer").build(),
            "OrderStatus", AttributeValue.builder().s("PACKING ITEMS").build()));

        putItem(Map.of(
            "CustomerId", AttributeValue.builder().s("bob@example.com").build(),
            "OrderId", AttributeValue.builder().n("5").build(),
            "OrderCreationDate", AttributeValue.builder().n("20150309").build(),
            "ProductCategory", AttributeValue.builder().s("Book").build(),
            "ProductName", AttributeValue.builder().s("How To Cook").build(),
            "OrderStatus", AttributeValue.builder().s("IN TRANSIT").build(),
            "ShipmentTrackingId", AttributeValue.builder().s("440185").build()));

        putItem(Map.of(
            "CustomerId", AttributeValue.builder().s("bob@example.com").build(),
            "OrderId", AttributeValue.builder().n("6").build(),
            "OrderCreationDate", AttributeValue.builder().n("20150318").build(),
            "ProductCategory", AttributeValue.builder().s("Luggage").build(),
            "ProductName", AttributeValue.builder().s("Really Big Suitcase").build(),
            "OrderStatus", AttributeValue.builder().s("DELIVERED").build(),
            "ShipmentTrackingId", AttributeValue.builder().s("893927").build()));

        putItem(Map.of(
            "CustomerId", AttributeValue.builder().s("bob@example.com").build(),
            "OrderId", AttributeValue.builder().n("7").build(),
            "OrderCreationDate", AttributeValue.builder().n("20150324").build(),
            "ProductCategory", AttributeValue.builder().s("Golf").build(),
            "ProductName", AttributeValue.builder().s("PGA Pro II").build(),
            "OrderStatus", AttributeValue.builder().s("OUT FOR DELIVERY").build(),
            "ShipmentTrackingId", AttributeValue.builder().s("383283").build()));
    }

    private static void putItem(Map<String, AttributeValue> item) {
        client.putItem(PutItemRequest.builder().tableName(tableName).item(item).build());
    }
}