🧩 MongoDB Practice Series – Filtering & Query Logic Exercises (Part 3)
Welcome to Part 3 of the MongoDB Practice Series.
In this lesson, you will practice advanced filtering techniques using MongoDB query operators.
These exercises will help you write more powerful and flexible queries.
🟢 Exercise 1: Use Comparison Operators
Problem:
Find all products where price is greater than 500.
Solution:
db.products.find({
price: { $gt: 500 }
})
Learning Goal: Practice using $gt (greater than).
🟡 Exercise 2: Range Query
Problem:
Find students whose age is between 18 and 25 (inclusive).
Solution:
db.students.find({
age: { $gte: 18, $lte: 25 }
})
Learning Goal: Combine $gte and $lte for range filtering.
🟡 Exercise 3: Use $in Operator
Problem:
Find courses where level is either "Beginner" or "Intermediate".
Solution:
db.courses.find({
level: { $in: ["Beginner", "Intermediate"] }
})
Learning Goal: Use $in for matching multiple values.
🔵 Exercise 4: Use Logical AND
Problem:
Find students who are older than 20 AND enrolled in "MCA".
Solution:
db.students.find({
age: { $gt: 20 },
course: "MCA"
})
Learning Goal: Understand that multiple conditions act as AND in MongoDB.
🔵 Exercise 5: Use $or Operator
Problem:
Find students who are either younger than 18 OR older than 25.
Solution:
db.students.find({
$or: [
{ age: { $lt: 18 } },
{ age: { $gt: 25 } }
]
})
Learning Goal: Use $or for alternative conditions.
🔴 Exercise 6: Exclude Specific Fields
Problem:
Retrieve all students but exclude the _id field.
Solution:
db.students.find(
{},
{ _id: 0 }
)
Learning Goal: Practice projection in queries.
🔴 Exercise 7: Search by Partial Match
Problem:
Find products where the name contains the word "Pro".
Solution:
db.products.find({
name: { $regex: "Pro" }
})
Learning Goal: Learn basic pattern matching using $regex.
🚀 Mini Challenge
Create a collection called employees with fields:
- name
- salary
- department
- experience
Then write queries to:
- Find employees with salary above 50,000
- Find employees in either "IT" or "HR"
- Find employees with experience between 2 and 5 years
Try solving without checking the examples above.
🎯 What’s Next?
In Part 4 of the MongoDB Practice Series, we will learn:
- Sorting data
- Limiting results
- Advanced query combinations
- Real-world filtering scenarios
Stay tuned for the next challenge!