Implicit AND with multiple conditions in MongoDB - Mini Project: Build & Apply

Implicit AND with multiple conditions in MongoDB

📖 Scenario: You are managing a small online bookstore database. You want to find books that match multiple criteria at the same time, such as books by a certain author and within a certain price range.

🎯 Goal: Build a MongoDB query that uses implicit AND to find books that meet multiple conditions simultaneously.

📋 What You'll Learn

Create a collection named books with specific book documents

Add a variable for the maximum price to filter books

Write a MongoDB query using implicit AND with multiple conditions

Complete the query to return only books matching all conditions

💡 Why This Matters

🌍 Real World

Filtering data in a database to find items that meet multiple criteria is common in online stores, libraries, and many apps.

💼 Career

Understanding how to write queries with multiple conditions is essential for database developers, data analysts, and backend engineers.

1

Create the books collection with sample documents

Create a MongoDB collection called books and insert these exact documents: { title: "The Great Gatsby", author: "F. Scott Fitzgerald", price: 10 }, { title: "1984", author: "George Orwell", price: 15 }, and { title: "To Kill a Mockingbird", author: "Harper Lee", price: 12 }.

MongoDB

// Insert the specified documents into the books collection
// Your code here

Need a hint?

Use db.books.insertMany() with an array of objects for the books.

2

Add a variable for the maximum price filter

Create a variable called maxPrice and set it to 12 to use as a price filter.

MongoDB

db.books.insertMany([
  { title: "The Great Gatsby", author: "F. Scott Fitzgerald", price: 10 },
  { title: "1984", author: "George Orwell", price: 15 },
  { title: "To Kill a Mockingbird", author: "Harper Lee", price: 12 }
])

// Create maxPrice variable
// Your code here

Need a hint?

Use const maxPrice = 12 to create the variable.

3

Write a MongoDB query using implicit AND with multiple conditions

Write a MongoDB query using db.books.find() to find books where the author is exactly "Harper Lee" and the price is less than or equal to maxPrice. Use implicit AND by specifying both conditions inside the same query object.

MongoDB

db.books.insertMany([
  { title: "The Great Gatsby", author: "F. Scott Fitzgerald", price: 10 },
  { title: "1984", author: "George Orwell", price: 15 },
  { title: "To Kill a Mockingbird", author: "Harper Lee", price: 12 }
])

const maxPrice = 12

// Write the query using implicit AND
// Your code here

Need a hint?

Put both conditions inside one object in db.books.find() to use implicit AND.

4

Complete the query to return matching books

Use db.books.find() with the query variable to find and return all books matching the conditions.

MongoDB

db.books.insertMany([
  { title: "The Great Gatsby", author: "F. Scott Fitzgerald", price: 10 },
  { title: "1984", author: "George Orwell", price: 15 },
  { title: "To Kill a Mockingbird", author: "Harper Lee", price: 12 }
])

const maxPrice = 12

const query = { author: "Harper Lee", price: { $lte: maxPrice } }

// Use db.books.find() with query to get matching books
// Your code here

Need a hint?

Pass the query object inside db.books.find() to get the results.