Also, I want to be able to query data that would be coonected to those nodes using the relationships at any nodes.
I have tried to go through the Mongodb documentation as well as other sources (mongodb community, stackoverflow, etc…) to see what has already been done but I could not find anything comparable to my problem. Is it even possible? If so, how? If not is there any alternative way I could try to achieve this result? I have considered using multiple documents but I was puzzled on which I could query it.
Since there wasn’t a reply to your message, I tried to run it by our documentation bot. Here is the response I got
To implement forward and backward relationships in MongoDB, you can use either embedded documents or references, depending on your application’s needs. Here’s a brief overview of both approaches:
Embedded Documents
Embedding is useful when you frequently query one entity to return data about another entity. This approach avoids the need for $lookup operations and can improve read performance.
Example:
Consider a blog application where each article has comments. You can embed comments directly within the article document:
db.articles.insertOne( { title: "My Favorite Vacation", date: ISODate("2023-06-02"), text: "We spent seven days in Italy...", comments: [ { name: "pedro123", text: "Great article!" }, { name: "jane_doe", text: "Thanks for sharing!" } ] })
References
Using references is beneficial when you frequently update related data. This approach reduces the write workload by updating data in a single place.
Example:
For the same blog application, you can store comments in a separate collection and reference them in the articles collection:
To implement forward and backward relationships, you can use a combination of embedding and referencing. For example, if you want to navigate from an article to its comments and from a comment back to its article, you can do the following:
Forward Relationship (Article to Comments): Embed comment IDs in the article document.
Backward Relationship (Comment to Article): Store the article ID in each comment document.
Example:
// Article document with forward relationshipdb.articles.insertOne( { title: "My Favorite Vacation", date: ISODate("2023-06-02"), text: "We spent seven days in Italy...", commentIds: [ ObjectId("60c72b2f9b1d8b3a4c8b4567"), ObjectId("60c72b2f9b1d8b3a4c8b4568") ] })// Comment documents with backward relationshipdb.comments.insertMany([ { _id: ObjectId("60c72b2f9b1d8b3a4c8b4567"), articleId: ObjectId("60c72b2f9b1d8b3a4c8b4569"), name: "pedro123", text: "Great article!" }, { _id: ObjectId("60c72b2f9b1d8b3a4c8b4568"), articleId: ObjectId("60c72b2f9b1d8b3a4c8b4569"), name: "jane_doe", text: "Thanks for sharing!" }])
This way, you can efficiently navigate between related data in both directions.
