30 lines
1.1 KiB
Markdown
30 lines
1.1 KiB
Markdown
---
|
|
tags:
|
|
- mongo-db
|
|
- databases
|
|
---
|
|
|
|
# MongoDB: Introduction
|
|
|
|
MongoDB is not a relational database system like SQL, instead it is
|
|
document-based which means you do not neeed to design database tables and
|
|
schema, you are simply storing data as JSON and there is no transformation of
|
|
the data.
|
|
|
|
Most of the notes on Mongo will introduce it within the context of Node.js
|
|
backend. We will be sending Javascript objects and arrays to Mongo and returning
|
|
them as JSON.
|
|
|
|
## Databases, collections, documents
|
|
|
|
Although Mongo is not a relational database it has a structure that we can
|
|
understand in relation to that paradigm. A **database** is obviously the overall
|
|
structure. It comprises **collections** which are organised sets of data that
|
|
are analagous to [tables](Relational_database_architecture.md#table)
|
|
in RDBs. Within each collection are a series of **documents** which we can think
|
|
of as being equivalent to [rows](Relational_database_architecture.md)
|
|
in RDB table: units that comprise the collection.
|
|
|
|
A document is a container comprising key-value pairs in the manner of an object.
|
|
|
|
|