是否可以更改 DynamoDB Table 中 Range 键的值？

Question

我知道这可能是一个非常愚蠢的问题，但我是 DynamoDB 的新手。

我怀疑是否可以在 DynamoDB 中更新范围键的值。

假设我的 Table 是 "TEST"

{
ID : PK/HK
Date : RK
Name : GSI 
Add : LSI
}

我想修改Date属性。

Table 中的初始值是：

{
ID = "344"
Date = "5656"
Name = "ABC"
}

运行下面这段代码。我可以更改 GSI 的 Name 属性。

Map<String,AttributeValue> item = new HashMap<String,AttributeValue>();
item.put("ID", new AttributeValue("344"));
item.put("Date", new AttributeValue("5656"));

Map<String,AttributeValueUpdate> item1 = new HashMap<String,AttributeValueUpdate>();

AttributeValueUpdate update = new AttributeValueUpdate().withValue(new AttributeValue("AMIT")).withAction("PUT");
item1.put("Name", update);


UpdateItemRequest updateItemreq = new UpdateItemRequest("Test",item,item1);
UpdateItemResult updateItemres = dynamoDBUSEast.updateItem(updateItemreq);

但是当我改变这一行时

item1.put("Name", update);

和

 item1.put("Date", update);

我遇到一些错误，因为

Exception in thread "main" com.amazonaws.AmazonServiceException: One or more parameter values were invalid: Cannot update attribute Date. This attribute is part of the key (Service: AmazonDynamoDBv2; Status Code: 400; Error Code: ValidationException; Request ID: HRRP24Q7C48AMD8ASAI992L6MBVV4KQNSO5AEMVJF66Q9ASUAAJG)
    at com.amazonaws.http.AmazonHttpClient.handleErrorResponse(AmazonHttpClient.java:820)
    at com.amazonaws.http.AmazonHttpClient.executeHelper(AmazonHttpClient.java:439)
    at com.amazonaws.http.AmazonHttpClient.execute(AmazonHttpClient.java:245)
    at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.invoke(AmazonDynamoDBClient.java:2908)
    at com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient.updateItem(AmazonDynamoDBClient.java:1256)

那么是否可以更改范围键值？

Answer 1

它有点隐蔽，但在 UpdateItem 的文档中它说： "You can use UpdateItem to update any nonkey attributes."

因此，目前更新项目主键的唯一方法是删除旧项目并写入新项目。

Answer 2

不，如异常消息所述，您 Cannot update attribute Date. This attribute is part of the key.

你也可以在AttributeUpdates documentation下面看到这个：

The names of attributes to be modified, the action to perform on each, and the new value for each. If you are updating an attribute that is an index key attribute for any indexes on that table, the attribute type must match the index key type defined in the AttributesDefinition of the table description. You can use UpdateItem to update any nonkey attributes.

文档指出您可以更新 "an attribute that is an index key attribute for any indexes on that table" 的任何属性，这意味着当您更新投影到索引上的属性时，即使它是该索引键的一部分，该索引也会进行更新以反映原始项目。

Answer 3

来自 AttributeValueUpdate

的文档

You cannot use UpdateItem to update any primary key attributes. Instead, you will need to delete the item, and then use PutItem to create a new item with new attributes.

Answer 4

这是我在 .net 中通过删除项目然后使用新 ID 重新创建来更新 ID 的实现。我假设 java 非常相似：

 // Based on https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/LowLevelDotNetItemsExample.html
public class UpdateId
{
    private static string tableName = "MyTableName";
    private static AmazonDynamoDBClient client = new AmazonDynamoDBClient();
    private static bool isVerbose = false;

    public static void ChangeId(string currentId, string newId)
    {
        try
        {
            var deletedItem = DeleteItem(currentId);

            if (deletedItem.Count == 0)
            {
                Console.WriteLine($"ERROR: Item to delete not found: {currentId}");
                return;
            }
            deletedItem["Id"] = new AttributeValue
            {
                S = newId
            };

            CreateItem(deletedItem);
            var updatedItem = RetrieveItem(newId);
            if (updatedItem.Count > 0 && updatedItem["Id"].S == newId)
            {
                Console.WriteLine($"Item id successfully changed from ({currentId}) to ({newId})");
            }
            else
            {
                Console.WriteLine($"ERROR: Item id didn't change from ({currentId}) to ({newId})");
            }
        }
        catch (Exception e)
        {
            Console.WriteLine(e.Message);
            Console.WriteLine("To continue, press Enter");
            Console.ReadLine();
        }
    }

    private static void CreateItem(Dictionary<string, AttributeValue> item)
    {
        var request = new PutItemRequest
        {
            TableName = tableName,
            Item = item
        };
        client.PutItem(request);
    }

    private static Dictionary<string, AttributeValue> RetrieveItem(string id)
    {
        var request = new GetItemRequest
        {
            TableName = tableName,
            Key = new Dictionary<string, AttributeValue>()
        {
            { "Id", new AttributeValue {
                  S = id
              } }
        },
            ConsistentRead = true
        };
        var response = client.GetItem(request);

        // Check the response.
        var attributeList = response.Item; // attribute list in the response.
        if (isVerbose)
        {
            Console.WriteLine("\nPrinting item after retrieving it ............");
            PrintItem(attributeList);
        }
        return attributeList;

    }

    private static Dictionary<string, AttributeValue> DeleteItem(string id)
    {
        var request = new DeleteItemRequest
        {
            TableName = tableName,
            Key = new Dictionary<string, AttributeValue>()
        {
            { "Id", new AttributeValue {
                  S = id
              } }
        },

            // Return the entire item as it appeared before the update.
            ReturnValues = "ALL_OLD",
      //      ExpressionAttributeNames = new Dictionary<string, string>()
      //  {
      //      {"#IP", "InPublication"}
      //  },
      //      ExpressionAttributeValues = new Dictionary<string, AttributeValue>()
      //  {
      //      {":inpub",new AttributeValue {
      //           BOOL = false
      //       }}
      //  },
      //      ConditionExpression = "#IP = :inpub"
        };

        var response = client.DeleteItem(request);

        // Check the response.
        var attributeList = response.Attributes; // Attribute list in the response.
                                                 // Print item.
        if (isVerbose)
        {
            Console.WriteLine("\nPrinting item that was just deleted ............");
            PrintItem(attributeList);
        }

        return attributeList;
    }

    private static void PrintItem(Dictionary<string, AttributeValue> attributeList)
    {
        foreach (KeyValuePair<string, AttributeValue> kvp in attributeList)
        {
            string attributeName = kvp.Key;
            AttributeValue value = kvp.Value;

            Console.WriteLine(
                attributeName + " " +
                (value.S == null ? "" : "S=[" + value.S + "]") +
                (value.N == null ? "" : "N=[" + value.N + "]") +
                (value.SS == null ? "" : "SS=[" + string.Join(",", value.SS.ToArray()) + "]") +
                (value.NS == null ? "" : "NS=[" + string.Join(",", value.NS.ToArray()) + "]")
                );
        }
        Console.WriteLine("************************************************");
    }
}

调用它只需这样做：

UpdateId.ChangeId("OriginalId", "NewId");

是否可以更改 DynamoDB Table 中 Range 键的值？

Is It possible to change value of Range key in DynamoDB Table?

java

amazon-dynamodb