MongoDB is “a scalable, high-performance, open source NoSQL database” using document-oriented storage with dynamic schemas that offer “simplicity and power.”
What that means:
■ Scalable, high performance: MongoDB is designed to scale horizontally, using lessexpensive
servers. With relational databases, the only easy way to scale your
database is to buy better hardware. With MongoDB you can easily add another
server to provide more capacity or performance.
■ Dynamic schemas: MongoDB doesn’t require a schema to define what
data can be stored in what tables, relational databases require. You can store any JSON
document in a collection. Individual documents within the same collection can
have completely different structures, and a document structure may be completely
changed during a document update.
■ Document-oriented storage: MongoDB stores data in the JSON document format
instead of in tables with columns and rows.
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