MongoDB : An Introduction

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MongoDB is an open-source, high-performance, document-oriented database. Documents are JSON-like data structures stored in a format called BSON (bsonspec.org).

Documents are stored in Collections, each of which resides in its own Database. Collections can be thought of as the equivalent of a table in an RDBMS. There are no fixed schemas in MongoDB, so documents with different “shapes” can be stored in the same Collection.

MongoDB features full index support (including secondary and compound indexes); indexes are specified per-Collection. There is a rich, document-based query language (see reverse) that leverages any indexes you've defined. MongoDB also provides complex atomic update modifiers (see reverse) to keep code contention-free.

Clustered setups are supported, including easy replication for scaling reads and providing high availability, as well as auto-sharding for write-scaling and large data-set sizes.

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