MongoDb - Modeling storage of users & post in a webapp - mongodb

Question

I'm quite new to nosql world.
If I have a very simple webapp with users authenticating & publishing posts, what's the mongodb(nosql) way to store users & posts on the nosql db?
Do I have (like in relationnal databases) to store users & posts each one in his own collection? Or store them in the same collection, on different documents? Or, finally with a redondant user infos (credentials) on each post he has published?

Answer 1

A way you could do it is to use two collection, a posts collection and a authors collection. They could look like the following:
Posts
{
title: "Post title",
body: "Content of the post",
author: "author_id",
date: "...",
comments: [
{
name: "name of the commenter",
email: "...",
comment: "..."
}],
tags: [
"tag1", "tag2, "tag3
]
}
Authors
{
"_id": "author_id",
"password": "..."
}
Of course, you can put it in a single collection, but #jcrade mentioned a reason why you would/should use two collections. Remember, that's NoSQL. You should design your database from an application point of you, that means ask yourself what data is consumed and how.

Answer 2

This post says it all:
https://www.mongodb.com/blog/post/6-rules-of-thumb-for-mongodb-schema-design-part-1
It really depends on your application, and how many posts you expect your users to have: if it's a one-to-few relationship, then probably using embedded documents (inside your users model) is the way to go. If it's one to many (up to a couple of thousands) then just embed an array of IDs in your users model. If it's more than that, then use the answer provided by Horizon_Net.
Read the post, and you get a pretty good idea of what you will have to do. Good luck!

Answer 3

When you are modeling nosql database you should think in 3 basic ideas
Desnormalization
Copy same data on multiple documents. in order to simplify/optimize query processing or to fit the user’s data into a particular data model
Aggregation
Embed data into documents for example (blog post and coments) in order to impact updates both in performance and consistency because mongo has one document consistency at time
Application level Joins
Create applicaciton level joins when its not good idea to agregate information (for example each post as idependent document will be really bad because we need to accces to the same resource)
to answer your question
Create two document one is blogPost with all the comments, and tags on it and user ui. Second User with all user information.