Why DynamoDB pairs with Lambda - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a DynamoDB client in AWS Lambda.

DynamoDB

const AWS = require('aws-sdk');
const dynamoDB = new AWS.DynamoDB.[1]();

Drag options to blanks, or click blank then click option'

AService

BClient

CConnector

DDocumentClient

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Client' instead of 'DocumentClient' causes errors.

The DocumentClient is used in Lambda to interact easily with DynamoDB tables.

2fill in blank

medium

Complete the code to define a Lambda function that reads an item from DynamoDB.

DynamoDB

exports.handler = async (event) => {
  const params = {
    TableName: 'Users',
    Key: { 'UserId': event.[1] }
  };
  const data = await dynamoDB.get(params).promise();
  return data.Item;
};

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AuserId

Bid

CUserId

Dkey

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'UserId' (case sensitive) instead of 'userId'.

The event object usually contains the user ID as userId to fetch the item.

3fill in blank

hard

Fix the error in the Lambda function that writes data to DynamoDB.

DynamoDB

exports.handler = async (event) => {
  const params = {
    TableName: 'Orders',
    Item: event.[1]
  };
  await dynamoDB.put(params).promise();
  return { statusCode: 200 };
};

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AItem

Bitem

Cdata

Dorder

Attempts:

3 left

💡 Hint

Common Mistakes

Using lowercase 'item' causes the function to fail.

The put method requires the key Item with capital 'I' to specify the data.

4fill in blank

hard

Fill both blanks to create a Lambda function that deletes an item from DynamoDB using the correct key and method.

DynamoDB

exports.handler = async (event) => {
  const params = {
    TableName: 'Products',
    [1]: { 'ProductId': event.productId }
  };
  await dynamoDB.[2](params).promise();
  return { statusCode: 200 };
};

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AKey

BItem

CdeleteItem

Ddelete

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Item' instead of 'Key' or 'deleteItem' instead of 'delete'.

The delete method deletes an item using the Key property to specify which item.

5fill in blank

hard

Fill the blanks to update an attribute in DynamoDB using Lambda.

DynamoDB

exports.handler = async (event) => {
  const params = {
    TableName: 'Employees',
    Key: { 'EmployeeId': event.employeeId },
    UpdateExpression: 'set [1] = :val',
    ExpressionAttributeValues: { ':val': event.newValue },
    ReturnValues: '{{BLANK_3}}'
  };
  const result = await dynamoDB.update(params).promise();
  return result.Attributes;
};

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ASalary

BN

CUPDATED_NEW

DS

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong attribute name or wrong ReturnValues string.

To update the 'Salary' attribute, return 'UPDATED_NEW' to get updated attributes.