如何在 dynamodb 中获取嵌套项目？

Question

I m using node typescript and local dynamodb. I'm unable to get a specific nested document. I m trying to get a post on the basis of id. I m using email as pk.

let params1:any= {
      TableName: "userTable",
      // Key: {
      //   email: email

      // },
      FilterExpression: "#posts[0].#id = :postId",
       // KeyConditionExpression: `#postId= :postId`,
      ExpressionAttributeNames: {
        "#posts": "posts",
        "#id": "id",

      },
      ExpressionAttributeValues: {
        ":postId": event.body.id

      },

     

    }

Answer 1

As per comments.

you need to remodel your table design by using composite key structure.

composite key = email = hash key, postId =  range/sort key

note:- if you are using post-operation to query DB, event.body.id should be req.body.id .

you can simply use dynamodb get operation to grab single record

const getRecordParams = {
    TableName: tableName,
    Key: {
      email: req.body.id,    // hash key
      postId: req.body.postId  //range key
    },
  };
const dynamoDbGetResults = await dynamoDb
      .get(getRecordParams)
      .promise();

dynamoDbGetResults will have your entire record from which you can extract your desired values.