--- id: 8b6h title: DynamoDB SDK commands tags: [AWS, databases, dynamodb] created: Sunday, June 23, 2024 --- # DynamoDB SDK commands The following commands are for using `@aws-sdk/client-dynamodb` (the JS SDK). ## Create client ```js import DynamoDBClient from "@aws-sdk/client-dynamodb"; const client = new DynamoDBClient({ region: "eu-west-2", accessKeyId: process.env.ACCESS_KEY_ID, secretAccessKey: process.env.ACCESS_KEY_ID, }); ``` ### DynamoDB Document Client The Document Client returns the data as a standard JSON document in the manner of a document-based NoSQL database. Without it, DynamoDB will return the data with type data which is unwieldy and hard to parse. To transform into a document structure: ```js import DynamoDBClient from "@aws-sdk/client-dynamodb"; import DynamoDBDocumentClient from "@aws-sdk/lib-dynamodb"; const client = new DynamoDBClient({ region: "eu-west-2", accessKeyId: process.env.ACCESS_KEY_ID, secretAccessKey: process.env.ACCESS_KEY_ID, }); const dynamoDbDocumentClient = DynamoDBDocumentClient.from(client); ``` ## Query a table Querying is the most performant and cost-effective method since it is an O(1) lookup against a partition key or secondary index. ```js const params = { TableName: "YourTableName", KeyConditionExpression: "#pk = :pk", ExpressionAttributeNames: { "#pk": "PrimaryKeyAttributeName" }, ExpressionAttributeValues: { ":pk": "PrimaryKeyValue" }, }; ``` ## Scan a table Scanning is less performant (O(n)) and most expensive since it requires checking every item in the database. ## Related notes