NoSQL databases are ideal for massive troves of unstructured data and are most often the first choice for cloud-native development or any project that depends on very large amounts of varying information.
But when trying to choose which NoSQL database to use, you’ll find the options can be a bit daunting. Which is right for your project, and what are the benefits? As soon as you start down the NoSQL rabbit hole, you’ll find quite a few options to select from. Of those options, two very often rise above the rest: MongoDB and Redis.
At first blush, you might think, “A database is a database, so it really doesn’t matter.” However, that line of thinking can get you into trouble. Imagine selecting the wrong database from the start, only to realize halfway through the software development lifecycle that the choice you made will not serve your project best. At that point, you might have to start over, wasting precious time.
Both MongoDB and Redis are outstanding NoSQL solutions, but they are not the same. Let’s dive in and see what makes each of these solutions unique and why you might want to use one over the other.
Redis or MongoDB? When to Use Each
When comparing MongoDB vs. Redis, you’ll want to take a look at four different aspects:
- Speed
- System requirements
- Scalability
- Storage
The choice between MongoDB and Redis is more straightforward than you might initially believe. Even though both of them are NoSQL databases, one could argue they operate more similarly to relational databases in certain contexts. They can store data efficiently, serving not just you but also your company and the applications you run. However, there are crucial considerations.
Complexity of Queries
If you’re looking at a use case that will require complex queries, MongoDB, with its document data model, stands out as the preferred choice. On the contrary, Redis, which some might say operates like a remote dictionary server, primarily focuses on single or multiple keys access. This design inherently restricts the breadth of its query functionalities. But, a significant upside to Redis’s primary key access model is its swiftness; it can retrieve stored data faster than MongoDB.
So, if you want an easier development trajectory for an app with complex queries, MongoDB is your choice. Yet, if you’re inclined towards quick results despite a little more upfront work, Redis should be your database choice.
Ease of use
There’s no way around this: MongoDB is easier to use than Redis. MongoDB not only offers a much more shallow learning curve, but it’s also easier to install. The caveat to this is that Redis is much more flexible. So, if you want to implement a NoSQL database that won’t have your development team pulling out their hair, MongoDB is the way to go. If, on the other hand, you want a lightning-fast database that offers greater flexibility (but a more challenging process), Redis is what you’re looking for.
Benefits of Using Redis and MongoDB — Comparative Chart
Let’s simplify this even further with a chart that displays the benefits of using each database.
| Criteria | MongoDB | Redis |
|---|---|---|
| Speed | High speed for large volumes of data, due to its document-oriented model | Extremely fast as data is stored in memory, ideal for caching and real-time applications |
| Scalability | Horizontally scalable through sharding | Supports master-slave replication and is vertically scalable |
| Transactional Data Integrity | Supports multi-document ACID transactions since version 4.0 | Transactions are atomic and support multiple operations, but does not support rollbacks |
| Memory Usage | Higher memory usage, data is stored on disk | Lower memory usage, data is stored in memory |
| Indexes | Supports secondary indexes and text search indexes | Does not inherently support secondary indexes |
| High Availability | Supports replication for high availability | Also supports replication for high availability |
| Query Language | Uses a proprietary, SQL-like query language (MQL) | Does not have a traditional query language, data is accessed through commands |
| Persistent Storage | Supports persistent storage | Supports both in-memory and persistent storage |
| Data Aggregation | Robust aggregation framework for complex data manipulation | Does not inherently support data aggregation |
| Cost | Open source, but commercial versions and hosting also available at a cost | Open source and free, enterprise and hosting options available at a cost |
| Ease of Use | Somewhat steep learning curve due to its unique document model and query language | Simpler to use due to its key-value store nature, but lacks some functionality of traditional DBMS |
| Security Features | Supports authentication, authorization, and encryption | Supports encryption, authentication, and allows for setting up data access permissions |
How to Select the Best for My Project
When should you use MongoDB? MongoDB is especially apt for rapidly changing data scenarios like rapid prototyping, startups, and hackathons, where peak performance might not be the top priority. Furthermore, if you’re in situations where a memory data store is essential or anticipate changes to your data models and schema frequently, MongoDB’s flexibility in not demanding a fixed schema can be beneficial.
On the other hand, Redis excels in caching scenarios and when your software development trajectory provides ample time for in-depth database planning. Summing it up: Need to kickstart something quickly? MongoDB should be on your radar. But if time is on your side and you’re diving deep into design and development, or if you’re looking at temporary data storage needs with performance as a paramount factor, Redis shines brightly. With Redis, it’s hard to match the performance benchmarks it sets.
