How to handle a Many-to-Many relationship with additional fields in MongoDB with Mongoose?

Question

Let's say that I have 2 entities (schemas): Store and Product. A store can have multiple products and a product can be found in multiple stores. I would like to have a quantity attribute / field that would tell me how many products of a sort does a store have. In SQL I would have something like this:

Table Store_X_Product
 » storeId
 » productId
 » quantity

So my question is: how do I create my schemas to handle this case?

Answer 1

You dont store that information usually. When SELECTING, use COUNT function, that way you don't even need to store data. If you really want to store quantity, add a column inside of a store table, but you will need to update it every time you INSERT a product