Firestore queries and indexes in GCP - Mini Project: Build & Apply

Firestore Queries and Indexes

📖 Scenario: You are building a simple app to manage a library's book collection using Google Firestore. You want to organize the data and run queries efficiently.

🎯 Goal: Create a Firestore collection with book data, add a configuration for filtering, write a query to find books by a specific author, and finally configure a composite index to support the query.

📋 What You'll Learn

Create a Firestore collection named books with specific book documents

Add a variable to filter books by the author "Jane Austen"

Write a Firestore query to get books where author equals the filter variable

Add a composite index configuration for author and publishedYear

💡 Why This Matters

🌍 Real World

Firestore is used to store and query data in many apps. Knowing how to structure data and indexes helps apps run fast and scale well.

💼 Career

Cloud engineers and developers often configure Firestore queries and indexes to optimize app performance and cost.

1

Create the Firestore collection with book documents

Create a Firestore collection named books with these exact documents: {"title": "Pride and Prejudice", "author": "Jane Austen", "publishedYear": 1813}, {"title": "Emma", "author": "Jane Austen", "publishedYear": 1815}, and {"title": "1984", "author": "George Orwell", "publishedYear": 1949}.

GCP

# Create the Firestore collection 'books' with the specified documents
# Your code here

Need a hint?

Use a list named books with dictionaries for each book.

2

Add a filter variable for author

Create a variable called author_filter and set it to the string "Jane Austen" to filter books by this author.

GCP

books = [
    {"title": "Pride and Prejudice", "author": "Jane Austen", "publishedYear": 1813},
    {"title": "Emma", "author": "Jane Austen", "publishedYear": 1815},
    {"title": "1984", "author": "George Orwell", "publishedYear": 1949}
]
# Create the variable 'author_filter' with value 'Jane Austen'
# Your code here

Need a hint?

Assign the exact string "Jane Austen" to author_filter.

3

Write a Firestore query to get books by the author filter

Write a Firestore query named query that filters the books collection where the author field equals the variable author_filter.

GCP

books = [
    {"title": "Pride and Prejudice", "author": "Jane Austen", "publishedYear": 1813},
    {"title": "Emma", "author": "Jane Austen", "publishedYear": 1815},
    {"title": "1984", "author": "George Orwell", "publishedYear": 1949}
]
author_filter = "Jane Austen"
# Write a query filtering books where author equals author_filter
# Your code here

Need a hint?

Use a list comprehension named query to filter books by author_filter.

4

Add a composite index configuration for author and publishedYear

Add a Firestore composite index configuration named composite_index as a dictionary with collectionId set to "books", and fields as a list of dictionaries for author ascending and publishedYear descending.

GCP

books = [
    {"title": "Pride and Prejudice", "author": "Jane Austen", "publishedYear": 1813},
    {"title": "Emma", "author": "Jane Austen", "publishedYear": 1815},
    {"title": "1984", "author": "George Orwell", "publishedYear": 1949}
]
author_filter = "Jane Austen"
query = [book for book in books if book["author"] == author_filter]
# Add the composite index configuration dictionary named 'composite_index'
# Your code here

Need a hint?

Define composite_index as a dictionary with the required keys and list of fields.