MongoDB is an open-source document-oriented database. MongoDB is a NoSQL database. It is written in C++. MongoDB is a free and cross-platform database. The community version of MongoDB is free and do not need to pay for the license. The paid version gives you support and access to some proprietary tools that makes it easy to work with the database.
Features of MongoDB are:
- Distributed database
- Highly available NoSQL database
- Supports horizontal scaling (Different parts of database table are distributed across multiple mongodb instances and load balanced)
- Geographic distribution is built-in and easy to use
MongoDB stores data in flexible format JSON-like documents. This means fields can vary from document to document, and data structure can be changed over time. Instead of using tables and rows like in a relational database, MongoDB architecture consists of collections and documents. Each database contains collections, each collection contains one or more documents. Each document can be different with varying number of fields.
How does a collection differ from a table?
Instead of tables, a MongoDB database stores its data in collections. A collection holds one or more BSON documents.
Documents are similar to records or rows in a relational database table. Each document has one or more fields, fields are similar to columns in a relational database table.
MongoDB licenses – Community versus Enterprise
You need to pay for the license for business use. Copyrights of source code are with the company.
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