DynamoDB Cheatsheet

Posted on: Dec 28, 2022

A cheatsheet of common functions called using the AWS SDK v3 DynamoDB DocumentClient.

Initial Setup

const { DynamoDBClient } = require("@aws-sdk/client-dynamodb");
const { DynamoDBDocumentClient } = require("@aws-sdk/lib-dynamodb");
const ddbClient = new DynamoDBClient({
  region: "<region>",
  credentials: {
    accessKeyId: "<acccessKeyId>",
    secretAccessKey: "<secretAccessKey>",
  },
});
const docClient = DynamoDBDocumentClient.from(ddbClient);

Query

The following expects a partition key of year_month.

const resp = await docClient.send(
  new QueryCommand({
    TableName: "<table_name>",
    KeyConditionExpression: "year_month = :ym",
    ExpressionAttributeValues: {
      ":ym": "2022-12",
    },
  })
);

const items = resp.Items;

Put

const data = {
  foo: "",
  bar: "",
};

await docClient.send(
  new PutCommand({
    TableName: "<table_name>",
    Item: {
      year_month: "2022-12",
      timestamp: dayjs().unix().toString(),
      ...data,
    },
  })
);