DynamoDBquery~30 mins

Querying GSI in DynamoDB - Mini Project: Build & Apply

Choose your learning style10 modes available

Learn Why Deep Visual Try Challenge Project Recall Time

Querying a Global Secondary Index (GSI) in DynamoDB

📖 Scenario: You are managing a DynamoDB table that stores information about books in a library. Each book has a unique BookID as the primary key. You want to quickly find books by their Author using a Global Secondary Index (GSI).

🎯 Goal: Build a DynamoDB query to retrieve all books by a specific author using the GSI named AuthorIndex.

📋 What You'll Learn

Create a DynamoDB table named Books with BookID as the primary key.

Create a GSI named AuthorIndex with Author as the partition key.

Write a query to find all books by the author 'J.K. Rowling' using the GSI.

Use the AWS SDK for Python (boto3) syntax for the query.

💡 Why This Matters

🌍 Real World

Many applications need to query data by attributes other than the primary key. GSIs let you do this efficiently in DynamoDB.

💼 Career

Understanding how to create and query GSIs is essential for backend developers and database engineers working with DynamoDB.

Progress0 / 4 steps

Create the DynamoDB table data structure

Create a dictionary called table_definition that defines a DynamoDB table named Books with BookID as the primary key of type String. Include an attribute definition for BookID of type S.

DynamoDB

# Your code here

Hint

Define table_definition as a dictionary with keys TableName, AttributeDefinitions, and KeySchema. Use BookID as the partition key.

Add the Global Secondary Index (GSI) configuration

Add a GlobalSecondaryIndexes key to the table_definition dictionary. Define one GSI named AuthorIndex with Author as the partition key of type S. Also add Author to the AttributeDefinitions list.

DynamoDB

table_definition = {
    'TableName': 'Books',
    'AttributeDefinitions': [
        {'AttributeName': 'BookID', 'AttributeType': 'S'}
    ],
    'KeySchema': [
        {'AttributeName': 'BookID', 'KeyType': 'HASH'}
    ]
}
# Add GlobalSecondaryIndexes and update AttributeDefinitions
# Your code here

Hint

Update table_definition to include GlobalSecondaryIndexes with the correct index name and key schema. Also add Author to AttributeDefinitions.

Write the query to find books by author

Create a dictionary called query_params to query the Books table using the AuthorIndex. Set the IndexName to 'AuthorIndex', the KeyConditionExpression to check Author equals 'J.K. Rowling', and use the expression attribute values accordingly.

DynamoDB

table_definition = {
    'TableName': 'Books',
    'AttributeDefinitions': [
        {'AttributeName': 'BookID', 'AttributeType': 'S'},
        {'AttributeName': 'Author', 'AttributeType': 'S'}
    ],
    'KeySchema': [
        {'AttributeName': 'BookID', 'KeyType': 'HASH'}
    ],
    'GlobalSecondaryIndexes': [
        {
            'IndexName': 'AuthorIndex',
            'KeySchema': [
                {'AttributeName': 'Author', 'KeyType': 'HASH'}
            ],
            'Projection': {
                'ProjectionType': 'ALL'
            },
            'ProvisionedThroughput': {
                'ReadCapacityUnits': 5,
                'WriteCapacityUnits': 5
            }
        }
    ]
}
# Create query_params dictionary to query AuthorIndex for 'J.K. Rowling'
# Your code here

Hint

Use boto3.dynamodb.conditions.Key to build the KeyConditionExpression. Set IndexName to 'AuthorIndex' and TableName to 'Books'.

Complete the query call to DynamoDB

Write a line of code that calls dynamodb_client.query() with query_params and stores the result in a variable called response. Assume dynamodb_client is already created.

DynamoDB

table_definition = {
    'TableName': 'Books',
    'AttributeDefinitions': [
        {'AttributeName': 'BookID', 'AttributeType': 'S'},
        {'AttributeName': 'Author', 'AttributeType': 'S'}
    ],
    'KeySchema': [
        {'AttributeName': 'BookID', 'KeyType': 'HASH'}
    ],
    'GlobalSecondaryIndexes': [
        {
            'IndexName': 'AuthorIndex',
            'KeySchema': [
                {'AttributeName': 'Author', 'KeyType': 'HASH'}
            ],
            'Projection': {
                'ProjectionType': 'ALL'
            },
            'ProvisionedThroughput': {
                'ReadCapacityUnits': 5,
                'WriteCapacityUnits': 5
            }
        }
    ]
}
from boto3.dynamodb.conditions import Key

query_params = {
    'TableName': 'Books',
    'IndexName': 'AuthorIndex',
    'KeyConditionExpression': Key('Author').eq('J.K. Rowling')
}
# Call dynamodb_client.query() with query_params and save to response
# Your code here

Hint

Use dynamodb_client.query(**query_params) to perform the query and assign the result to response.

Practice

(1/5)

1. What is the main purpose of querying a Global Secondary Index (GSI) in DynamoDB?

easy

A. To delete items from the table

B. To create a backup of the table

C. To update the primary key of items

D. To find items using an alternate key without scanning the whole table

Recommended

Ready to prove it?

Pass the test and this pattern moves unknown strong while earning +1 Grip toward your certificate.

10 questions~5 mineasy hard

Querying GSI in DynamoDB - Mini Project: Build & Apply

Practice

Solution

Step 1: Understand what a GSI is used for

Step 2: Identify the main benefit of querying a GSI

Final Answer:

Quick Check:

Solution

Step 1: Recall the correct parameter name for GSI in DynamoDB query

Step 2: Check the options for correct syntax

Final Answer:

Quick Check:

Solution

Step 1: Understand the query parameters

Step 2: Determine what the query returns

Final Answer:

Quick Check:

Solution

Step 1: Understand GSI key requirements

Step 2: Identify the error cause

Final Answer:

Quick Check:

Solution

Step 1: Use the GSI name and correct key condition

Step 2: Check logical operators and expressions

Step 3: Verify FilterExpression usage

Final Answer:

Quick Check:

Ready to prove it?