Effective mongodb + mongoose. Schema design

Disclaimer: I've embarked on this simply as a challenge to myself. See the <rant> below for an explanation as to why I disagree with your approach.

First step to getting a solid grasp on No-SQL is throwing out terms like "denormalize" – they simply do not apply in a document based data store. Another important concept to understand is there are no JOINS in MongoDB, so you have to change the way you think about your data completely to adjust.

The best way to solve your problem with mongoose is to setup collections for Quotes and Items separately. Then we can set up references between these collections to "link" the documents together.

var mongoose = require('mongoose');var Schema = mongoose.Schema;var quoteSchema = new Schema({  items: [{ type: Schema.Types.ObjectId, ref: 'Item' }]});var itemSchema = new Schema({});

That handles your Quotes -> Items "relationship". To get the Orders setup, you could use an array of embedded documents like you've indicated, but if you ever decided to start querying/indexing Orders, you'd be up a certain creek without a paddle. Again, we can solve this with references:

var itemSchema = new Schema({  orders: [{ type: Schema.Types.ObjectId, ref: 'Order' }]});var orderSchema = new Schema({  quarter: String});

Now you can use population to get what you need:

Item  .findById(id)  .populate({    path: 'orders',    match: { quarter: 'Q1-14' }  })  .exec(function (err, item) {    console.log(item.orders); // logs an array of orders from Q1-14  });

Trouble with references is that you are actually hitting the DB with a read instruction twice, once to find the parent document, and then once to populate its references.

You can read more about refs and population here: http://mongoosejs.com/docs/populate.html

<rant>

I could go on for hours why you should stick to an RDBMS for this kind of data. Especially when the defense for the choice is a lack of an ORM and Mongo being "all the rage." Engineers pick the best tech for the solution, not because a certain tech is trending. Its the difference between weekend hackery and creating Enterprise level products. Don't get me wrong, this is not to trash No-SQL – the largest codebase I maintain is built on NodeJS and MongoDB. However, I chose those technologies because they were the right technologies for my document based problem. If my data had been a relational ordering system like yours, I'd ditch Mongo in a heartbeat.

</rant>