MongoDB is an open source database NoSQL that uses a document-oriented data model and a semi-structured query language. This database is written in C++.

NoSQL ("non SQL" or "not only SQL") is an approach to database design that enables the storage and querying of data outside the traditional structures found in relational databases. In a NoSQL database, data is stored in an unstructured form mainly as key-value.

1. Key-Value store: It's a typical NoSQL database that stores data as key-value pairs, where each element has a key that's unique in the set of data, while the value is an array of data.

   Some examples of this type of database are Redis and Memcached that are open source.

2. Wide-Column store: This type of database store information in columns, enabling users to access only the specific columns they need. This database tries to solve for the shortcomings of key-value and document store.

   Some examples of this type of database are Apache HBase and Apache Cassandra that are open source.

3. Graph store: This type of database stores all its data in a graph, each piece of data is stored as a node of the Graph and its relations to other nodes is established by means of the graph edges. Although this type of database talks about relations, it is still NoSQL because it is unstructured data.

   An example of such a database is Neo4j which is open source and built on java.

4. Document store: As suggested by the name of this type of database, the data is stored in documents that typically use XML, JSON or BSON formats to store the information in a semi-structured form, making it easy to access and not having to respect any particular data structure between documents.

   An example of such a database is MongoDB which is open source.

The internal architecture of MongoDB is built on the concept of collections and documents. The most atomic unit is a set of key-value pairs that allows documents to have different fields between them. The format used by MongoDB in its documents is BSON which is a binary representation of the traditional JSON format.

• Database: It is the physical container for the data. Each database has its own set of files on the file system and multiple databases can exist on a single MongoDB server.

• Collection: It is a group of documents that are intended for the same purpose. All collections exist within a single database and there are no defined schemas in these.

• Document: A set of key-value pairs that is called a document. Documents are composed of dynamic schemas that allow the same collection to contain documents with different structures.

(Source: Pragimtech MongoDB Tutorial)

MongoDB is very flexible and allows you to combine and store multivariate data without compromising the powerful indexing, fast data access and validation rules it has.

• No downtime while the application is being scaled
• Performs in-memory processing
• Text search
• Multiple Servers
• Graph processing
• Global replication
• Economical

MongoDB can be installed on the following platforms.

Install dependecies:

sudo apt update
sudo apt install dirmngr gnupg apt-transport-https ca-certificates software-properties-common

Add MongoDB GPG key:

sudo wget -qO - https://www.mongodb.org/static/pgp/server-6.0.asc | sudo apt-key add -

Create a source list for MongoDB:

echo "deb [ arch=amd64,arm64 ] https://repo.mongodb.org/apt/ubuntu focal/mongodb-org/6.0 multiverse" | sudo tee /etc/apt/sources.list.d/mongodb-org-6.0.list

Update package:

sudo apt update

Install MongoDB:

sudo apt install mongodb-org

Tap MongoDB Homebrew:

brew tap mongodb/brew

Update Homebrew:

brew update

Install MongoDB:

brew install [email protected]

Pull image:

sudo docker pull mongo

Run image:

docker run --name some-mongo -e MONGO_INITDB_ROOT_USERNAME='root' -e MONGO_INITDB_ROOT_PASSWORD='example' -p 27017:27017 -d mongo

MongoDB Atlas is a cloud clustering service that supports multiple providers such as AWS, Azure and GCP, with Atlas you can have a MongoDB cluster in a few steps and leaving aside all kinds of worries about hardware and software upgrades.

Using MongoDB is easy with its officially drivers and libraries. In this dojo in the languages folder you can find a practical example of how to use MongoDB with Python, Nodejs, go and MongoDB Shell.

Other languages officially supported by MongoDB:

• C
• C++
• C#
• Java
• PHP
• Ruby
• Rust
• Scala
• Swift

MongoDB Compass is a powerful GUI for querying, aggregating, and analyzing your MongoDB data in a visual environment.

Compass is free to use and open source, and can be run on macOS, Windows, and Linux.

Download:

wget https://downloads.mongodb.com/compass/mongodb-compass_1.35.0_amd64.deb

Install:

sudo dpkg -i mongodb-compass_1.35.0_amd64.deb

On the official MongoDB website you will find the executables to install on Windows and macOS.