MongoDB vs Redis: Comparison

MongoDB vs Redis: What does a comparison of the two very powerful NoSQL databases look like, each with its own strengths? While MongoDB is more intended for processing large amounts of data, Redis stands out for its speed. It is possible to combine the two solutions.

MongoDB: Scalability and Flexibility

MongoDB, derived from the English term « huMongous » (gigantic), is known to be one of the most popular and appreciated NoSQL systems in the world. The database was designed in 2009 by the company 10gen (now MongoDB Inc.) with the aim of store large and diverse volumes of data in a clear manner and manage them securely. MongoDB stands out above all for its high horizontal scalability and thus its inherent flexibility. MongoDB is an open source database management system written in C++ and offered by the Server Side Public License in free and proprietary licenses, continuously developed.

Redis: The Fast NoSQL Solution

If there is one thing that the two solutions MongoDB vs Redis share in common, it is their year of publication: Redis was also published in 2009. The name Redis which comes from « REmote DIctionary Server » was programmed by Salvatore Sanfilippo at ANSI (American National Standards Institute). Redis is also an open source solution (under the 3-clause BSD license) and works in a non-relational way, that is to say by giving up (as much as possible) the classic table model. This system has a simple interface and seduces us with its ease of use and speed. While the system may seem simple at first glance, it can be extended in many ways. This is why Redis is one of the most popular key-value stores in the world.

What are the areas of application?

MongoDB is theabsolute expert in the field of Big Data. If you need to manage a large volume of data and different types of data, this NoSQL system is the solution for your needs. If your needs grow over time, MongoDB is designed to grow with you. MongoDB has established itself, especially in content management, e-commerce solutions and applications that must remain freely configurable and require constant analysis in real time.

In comparison, Redis is rather ahead of the speed factor. This system stores data in key-value pairs and supports many data types. common reaction times of less than a thousandth of a second that allow to process countless simultaneous requests at the same time are the great strength of Redis. This makes Redis an optimal choice for caching or session storage where the used data of different types must be made available as quickly as possible. Other areas where Redis is in an advantageous position are Messenger and chat rooms, (online) gaming, real-time analytics, streaming, financial services and the Internet of Things. Redis has both horizontal and vertical scalability.

What are the operating modes?

The MongoDB vs Redis confrontation reveals differences in approach and operation. Both systems are based on a non-relational approach but they interpret it in two distinct ways: MongoDB stores data in documents in BSON format and groups these documents into collections. This data can be structured, semi-structured, or unstructured. Documents consist of key-value pairs, although the key is always a string and the value can be other documents, arrays, boolean values, or other data types, among others. To ensure high availability, MongoDB uses so-called sharding, which splits data across multiple nodes. Queries are made using the MongoDB query language.

The fact that all data is stored in RAM memory and that they are thus immediately available allows Redis to achieve its extremely high speed. In contrast to other solutions, the latency is very low here (but the memory space is at the same time limited). Like its competitor in the MongoDB vs Redis comparison, Redis also uses key-value pairs. The in-memory database supports different values ​​and data structures, such as hashes, lists, sets, streams and strings. The storage of the respective keys is done in a dictionary and for the processing of multiple values, a parser is used. Modules exist for additional query functions.

Performance

MongoDB is a database that allows for high-speed read and write queries. The schema-less structure of the NoSQL solution does not cause any slowdowns in the event of large data volumes. This speed is also achieved by combining different memories. But the in-memory database is generally significantly faster in our MongoDB vs Redis comparison. Storing data directly in RAM makes it available. This is why Redis is ideal for viewing content as quickly as possible. But it does take up more RAM: the consumption of 4 GB per 100,000 assets is almost four times higher than that of MongoDB.

Scalability

When comparing the scalability possibilities of MongoDB vs Redis, a new face appears. Both systems offer good options overall, especially MongoDB which stands out in this area. The database is designed in such a way that it can evolve without limits horizontally and thus manage the most varied types of data. Sharding splits the data by making it available on the one hand and being able to process it very efficiently on the other hand. Redis certainly offers horizontal and vertical scalability but only uses one shard at a time in series. Only Hashed Sharding is possible and management must be done manually.

Availability

Sharding has a positive effect on the availability of data in a MongoDB database. The system uses replication phrases and allows users to create up to 50 replications of a file. These are then stored on different node points. The automatic switching functions not only allow to determine a primary point, but also to replace it immediately and automatically in the event of a failure.

Redis also offers high availability and uses different node points if needed. An automatic switchover is however ruled out.unless the administrator sets it up manually. Otherwise, the failover must also be initiated autonomously.

Compatibility

When comparing MongoDB vs Redis, we realize that their biggest common point is the strong compatibility with operating systems and programming languages. As cross-platform systems, both rivals work with Linux, macOS, and Windows. MongoDB also supports Solaris and Redis offers BSD. The choice of possible programming language is considerable in both cases.

Query language

A query is executed differently between MongoDB and Redis. MongoDB works with its own MongoDB Query Language (MQL) which supports a syntax similar to JSON format. In fact, even data parsing and queries across multiple domains and keys are possible. Redis, however, is giving up its own query language. and instead uses simple commands that make searching for data easier and are even supposed to speed it up. This makes only key-value queries possible by default. You have to integrate other modules to have additional options.

Two open source databases

Another thing MongoDB vs Redis have in common is their open source approach. Both systems rely on free standards that are used and continually developed by an engaged community. MongoDB provides additional commercial versions such as Enterprise or Atlas (for use in the Cloud). These offer additional security features as well as professional support.

MongoDB vs Redis: Which Companies Use Them?

There are many large companies that use one or the other of our MongoDB vs Redis competitors. The most well-known companies that use MongoDB are:

• Adobe
• Amadeus
• AppScale
• Craftbase
• Disney
• Etsy
• Foursquare
• Lyft
• MTV
• The New York Times
• Via Varejo

Redis is used by these companies and platforms, among others:

• Airbnb
• Craigslist
• GitHub
• HelloFresh
• InstaCart
• Instagram
• Pinterest
• Slack
• Snapchat
• StackOverflow
• Trello
• Uber
• X (formerly Twitter)

MongoDB vs Redis: Which One is Right for You?

What is the result of our MongoDB vs Redis duel? The answer to this question is closely linked to your requirements. If you need a high-speed database with immediate data availability, we recommend you opt for Redis. If, on the contrary, you value Big Data and flexibility, opt for MongoDB instead. When in doubt, you don't need to make a decision: used together, MongoDB and Redis allow optimal work and can even pool their strengths. This way, you benefit from the speed of Redis while benefiting from the scalability options of MongoDB.