Question

有没有办法在不使用UpdateExpression的情况下更新DynamoDB中的项目？

现在，我有这样的事情：

Map<String, AttributeValue> keys = new HashMap<String, AttributeValue>();
keys.put("id", new AttributeValue().withS("123456"));

Map<String, AttributeValue> expressionAttributesValues = new HashMap<String,ATtributeValue>();
expressionAttributes.pput(":newMarks", new AttributeValue().withS("60"));

    UpdateItemRequest request = new UpdateItemRequest().     
withTableName("MyTable").
withKey(keys).
withUpdateExpression("set marks = :newMarks").
withExpressionAttributeValues(expressAttributeValues);

DynamoDB.updateItem(request);

Answer 1

我真的不明白为什么你不想使用UpdateExpression，这可能对你有帮助。

这用于添加新项目，但我认为它可以提供帮助。

http://docs.aws.amazon.com/amazondynamodb/latest/gettingstartedguide/GettingStarted.Java.03.html#GettingStarted.Java.03.01

这是Scala上的示例

def step31(): Unit ={
  val awsCredentials: BasicAWSCredentials = new BasicAWSCredentials("XXXX", "XXXXX")
  val client: AmazonDynamoDBClient = new AmazonDynamoDBClient(awsCredentials)

  val dynamoDB: DynamoDB = new DynamoDB(client)
  val tableName = "Movies"
  val table: Table = dynamoDB.getTable(tableName)

  val year = 2015
  val title = "The Big New Movie"

  System.out.println("Adding a new item...")
  val outcome: PutItemOutcome = table.putItem(new Item()
  .withPrimaryKey("year", year, "title", title)
  .withJSON("info", Json.obj("plot" -> "Something happens.").toString()))
  //      .withJSON("info", "{\"plot\" : \"Something happens.\"}"))

  System.out.println("PutItem succeeded:\n" + outcome.getPutItemResult)
}

在没有updateExpression的情况下更新dynamo中的项目

1 个答案: