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