How to get the last N records in mongodb?

Cover Image for How to get the last N records in mongodb?
Matheus Mello
Matheus Mello
published a few days ago. updated a few hours ago

📜 MongoDB: How to Get the Last N Records

Hey there, tech enthusiasts! 👋 Are you struggling with getting the last N records in MongoDB? Don't worry, you're not alone! This is a common issue that many developers face, but fear not - I've got you covered! In this blog post, I'll walk you through easy solutions and provide code examples to help you retrieve the desired data. So, let's dive right in! 💪

The Problem 🤔

By default, the MongoDB find() operation retrieves records from the beginning, making it a bit tricky to fetch the last N records. Additionally, if you want the result ordered from less recent to most recent, you're in for an extra challenge. That's a lot to tackle, but don't fret! I've got some amazing solutions for you. 💡

Solution 1: Use sort() and limit() 🗂️

The first approach involves combining the sort() and limit() methods to fetch the last N records:

db.collection.find().sort({ _id: -1 }).limit(N)

In the above code snippet, replace collection with the actual name of your collection and N with the number of records you wish to retrieve. By sorting the records in descending order based on their unique _id using -1, we ensure that the most recent entries appear first. The limit() method restricts the result to the specified number, giving you the last N records you desire. 📃

Solution 2: Utilize count() and skip() 😎

Another approach involves using count() to determine the total number of records, and then applying skip() to retrieve the required documents:

const totalCount = db.collection.count();
const skipCount = totalCount - N;

db.collection.find().skip(skipCount);

In the code snippet above, we first calculate totalCount by using the count() function on the collection. We then compute the skipCount by subtracting the desired number of records (N) from the totalCount. Finally, by utilizing skip() in conjunction with find(), we can retrieve the last N records without explicitly sorting them. 🧮

Solution 3: Leverage aggregate() 🔄

If you're seeking a more robust solution, aggregate() is here to save the day! We can leverage the $sort and $limit aggregation operators to fetch the last N records:

db.collection.aggregate([
  { $sort: { _id: -1 } },
  { $limit: N }
]);

In the code snippet above, the aggregation pipeline utilizes $sort to sort the records based on their _id in descending order. Next, $limit is applied, restricting the result to the specified number (N) and giving us our desired output. 🌪️

Engage and share your experience! 📣

There you have it! Three simple yet effective solutions to get the last N records in MongoDB. Give them a try, and let me know your thoughts! Have any other strategies or questions? Share your experience in the comments section below. Your feedback could help fellow developers facing similar challenges! 👇

Keep exploring, keep coding! 💻✨



More Stories

Cover Image for How can I echo a newline in a batch file?

How can I echo a newline in a batch file?

updated a few hours ago
batch-filenewlinewindows

🔥 💻 🆒 Title: "Getting a Fresh Start: How to Echo a Newline in a Batch File" Introduction: Hey there, tech enthusiasts! Have you ever found yourself in a sticky situation with your batch file output? We've got your back! In this exciting blog post, we

Matheus Mello
Matheus Mello
Cover Image for How do I run Redis on Windows?

How do I run Redis on Windows?

updated a few hours ago
rediswindows

# Running Redis on Windows: Easy Solutions for Redis Enthusiasts! 🚀 Redis is a powerful and popular in-memory data structure store that offers blazing-fast performance and versatility. However, if you're a Windows user, you might have stumbled upon the c

Matheus Mello
Matheus Mello
Cover Image for Best way to strip punctuation from a string

Best way to strip punctuation from a string

updated a few hours ago
punctuationpythonstring

# The Art of Stripping Punctuation: Simplifying Your Strings 💥✂️ Are you tired of dealing with pesky punctuation marks that cause chaos in your strings? Have no fear, for we have a solution that will strip those buggers away and leave your texts clean an

Matheus Mello
Matheus Mello
Cover Image for Purge or recreate a Ruby on Rails database

Purge or recreate a Ruby on Rails database

updated a few hours ago
rakeruby-on-railsruby-on-rails-3

# Purge or Recreate a Ruby on Rails Database: A Simple Guide 🚀 So, you have a Ruby on Rails database that's full of data, and you're now considering deleting everything and starting from scratch. Should you purge the database or recreate it? 🤔 Well, my

Matheus Mello
Matheus Mello