MongoDB – Part 2 – Databases

OK. So in part 1 we covered a bunch of MongoDB basics. In this part, I plan on covering in detail the core MongoDB databases, what collections they have and what they’re used for.

When you first install MongoDB, two databases are created for you called admin and local. They don’t contain many collections and may not even contain any to begin with, however don’t worry about this, Mongo will create them as an when it needs them.

The third core database is called config. Config databases are a little more complicated, in that they can only be accessed when connected to a shard instead of a particular daemon. I haven’t covered shards yet. But for now just think of shards as individual mongod nodes, that all together form your data set. How this happens is very customisable, these customisable setting are stored in the config database. I’ll cover shards in great detail in a separate post.

Edit: Learn about MongoDB shards

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MongoDB – Part 1 – Collections, CRUD, Modifiers, Commands

Recently I’ve been posting a lot of articles about database and more specifically NoSQL. I’ve given a quick overview of each of the NoSQL database types as well as an overview of common concepts that appear throughout most NoSQL databases. Now I want to focus on a specific NoSQL database and I have Chosen MongoDB.

MongoDB is the most popular NoSQL database out there right now and you don’t have to take my word for it. Looking at Google Trends, you can see that MongoDB is getting more searches than Redis, Neo4j and Cassandra combined. Each of these databases are leading the way for their own database model (key-value, document, column and graph). So if you plan on learning a new database, MongoDB is without a doubt a fantastic choice. I’ve personally really enjoyed working with it the last 3 months and can see it being a popular choice for a very long time.

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NoSQL Essentials – Part 3 – Document databases

Document Databases

Document databases are debatably the most talked about NoSQL database type at the time of writing. They’re easy to understand and really easy to work with. They offer all the benefits of using a key-value database (nearly), plus a lot more. Some of the most popular key-value databases currently includes, MongoDB, CouchDB, Terrastore, OrientDB and RavenDB. In this article I am going to be focusing on MongoDB.

Some people love Mongo, some people hate it, I’ve only played with it, but given it’s the most widely used NoSQL database and the most valued by employers. It’s certainly worth knowing a little about.

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