MongoDB Aggregation $sort

MongoDB Aggregation $sort 🔃

What does $sort do?

• Orders documents ascending or descending

• Works on single or multiple fields

• Commonly combined with $limit, $skip, $group

• Similar to ORDER BY in SQL

Basic Syntax

📌 -1 = Descending

1️⃣ Sort by a Single Field

Example: Sort students by age (ascending)

Descending

2️⃣ Sort by Multiple Fields

Example: Sort by course (ASC) then age (DESC)

📌 First sorts by course, then by age within each course.

3️⃣ $sort with $limit (Top N Records)

Top 5 oldest students

⚠️ $sort must come before $limit.

4️⃣ $sort After $group

Example: Courses with most students

5️⃣ $sort with $match (Best Practice 👍)

📌 Filter first, then sort → better performance

6️⃣ Sorting Text Fields (A–Z / Z–A)

SQL vs MongoDB $sort

SQL

MongoDB

$sort vs sort() in find()

Example:

Performance Tips ⚡

• Use indexes on sort fields

• Place $match before $sort

• Avoid sorting large datasets without indexes

Common Mistakes ❌

• Using $limit before $sort

• Sorting without indexes on big collections

• Expecting numeric sort on string fields

Quick Recap 🧠