要在本地进行DynamoDB单元测试并确保GSI（全局二级索引）已更新，您可以使用AWS SDK提供的模拟器和本地数据库。以下是使用Java SDK进行DynamoDB单元测试的示例代码：

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

import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
import software.amazon.awssdk.services.dynamodb.model.AttributeValue;
import software.amazon.awssdk.services.dynamodb.model.CreateTableRequest;
import software.amazon.awssdk.services.dynamodb.model.CreateTableResponse;
import software.amazon.awssdk.services.dynamodb.model.DeleteTableRequest;
import software.amazon.awssdk.services.dynamodb.model.DeleteTableResponse;
import software.amazon.awssdk.services.dynamodb.model.DescribeTableRequest;
import software.amazon.awssdk.services.dynamodb.model.DescribeTableResponse;
import software.amazon.awssdk.services.dynamodb.model.GlobalSecondaryIndex;
import software.amazon.awssdk.services.dynamodb.model.KeySchemaElement;
import software.amazon.awssdk.services.dynamodb.model.Projection;
import software.amazon.awssdk.services.dynamodb.model.ProvisionedThroughput;
import software.amazon.awssdk.services.dynamodb.model.PutItemRequest;
import software.amazon.awssdk.services.dynamodb.model.PutItemResponse;
import software.amazon.awssdk.services.dynamodb.model.ScanRequest;
import software.amazon.awssdk.services.dynamodb.model.ScanResponse;
import software.amazon.awssdk.services.dynamodb.model.TableDescription;
import software.amazon.awssdk.services.dynamodb.model.TableStatus;
import software.amazon.awssdk.services.dynamodb.model.AmazonDynamoDbException;

public class DynamoDBTest {

    private DynamoDbClient dynamoDbClient;

    public DynamoDBTest(DynamoDbClient dynamoDbClient) {
        this.dynamoDbClient = dynamoDbClient;
    }

    public void createTable(String tableName, String gsiName) {
        CreateTableRequest createTableRequest = CreateTableRequest.builder()
                .tableName(tableName)
                .keySchema(KeySchemaElement.builder().attributeName("id").keyType("HASH").build())
                .attributeDefinitions(AttributeDefinition.builder().attributeName("id").attributeType("N").build())
                .provisionedThroughput(ProvisionedThroughput.builder()
                        .readCapacityUnits(5L)
                        .writeCapacityUnits(5L)
                        .build())
                .globalSecondaryIndexes(GlobalSecondaryIndex.builder()
                        .indexName(gsiName)
                        .keySchema(KeySchemaElement.builder().attributeName("name").keyType("HASH").build())
                        .projection(Projection.builder().projectionType("ALL").build())
                        .provisionedThroughput(ProvisionedThroughput.builder()
                                .readCapacityUnits(5L)
                                .writeCapacityUnits(5L)
                                .build())
                        .build())
                .build();

        CreateTableResponse createTableResponse = dynamoDbClient.createTable(createTableRequest);
        System.out.println("Table created: " + createTableResponse.tableDescription().tableName());
    }

    public void deleteTable(String tableName) {
        DeleteTableRequest deleteTableRequest = DeleteTableRequest.builder()
                .tableName(tableName)
                .build();

        DeleteTableResponse deleteTableResponse = dynamoDbClient.deleteTable(deleteTableRequest);
        System.out.println("Table deleted: " + deleteTableResponse.tableDescription().tableName());
    }

    public void putItem(String tableName, String gsiName) {
        Map item = new HashMap<>();
        item.put("id", AttributeValue.builder().n("1").build());
        item.put("name", AttributeValue.builder().s("John").build());

        PutItemRequest putItemRequest = PutItemRequest.builder()
                .tableName(tableName)
                .item(item)
                .build();

        PutItemResponse putItemResponse = dynamoDbClient.putItem(putItemRequest);
        System.out.println("Item added: " + putItemResponse.attributes());

        // Wait for GSI to be updated
        while (true) {
            DescribeTableRequest describeTableRequest = DescribeTableRequest.builder()
                    .tableName(tableName)
                    .build();

            DescribeTableResponse describeTableResponse = dynamoDbClient.describeTable(describeTableRequest);
            TableDescription tableDescription = describeTableResponse.table();

            if (tableDescription.tableStatus() == TableStatus.ACTIVE) {
                System.out.println("GSI updated");
                break;
            }

            try {
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    public void scanTable(String tableName) {
        ScanRequest scanRequest = ScanRequest.builder()
                .tableName(tableName)
                .build();

        ScanResponse scanResponse = dynamoDbClient.scan(scanRequest);
        System.out.println("Scanned items: " + scanResponse.items());
    }

    public