Dynamo db分页 [英] Dynamo db pagination

问题描述

我想使用 aws-sdk DocumentClient（）
在dynamodb中使用分页，我正在使用node.js。

I want to use pagination in dynamodb using aws-sdk DocumentClient() I am using node.js.

我要做的是先获取10个项目，然后将这些值返回给用户。在该用户发出新请求后，他告诉服务器从10开始，服务器从10到20再获得10，然后将响应返回。我已经尝试过 LastEvaluatedKey ，但是我的情况有所不同。有什么方法可以告诉dynamodb从特定项开始，例如1，然后设置 Limit：10 。

What I want to do is get first 10 items and then return these value to the user. After that user makes a new request in which he tell the server to start from 10 and the server get other 10 from 10 to 20 and return the response back. I have tried the LastEvaluatedKey But my scenario is different. Is there any way that I can tell dynamodb to start from specific Item e.g 1 and then set Limit: 10.

推荐答案

我找到了解决此问题的方法。您需要从dynamodb响应中获取 LastEvaluatedKey 并将其发送回前端，然后您的前端应发送 LastEvaluatedKey 在参数中，您可以将其用作 ExclusiveStartKey 。

I found a way to work around this. You need to get the LastEvaluatedKey from the dynamodb response and send it back to the front-end then your front-end should send the LastEvaluatedKey in params and you can use it as ExclusiveStartKey.

getItems(pageSize, lastItem?) {
    try {
      const params = {
        TableName: 'User',
        Limit: pageSize,
      };
      if (lastItem) {
        params.ExclusiveStartKey = { item_id: lastItem};
      }
      const response = await dynamoDb.scan(params).promise();
      return {
         items: response.Items,
         lastItem: response.LastEvaluatedKey
      }

    } catch (error) {
      throw error;
    }

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