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Discussion on: Designing a better architecture for a Node.js API

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Replies for: HI Thiago , I am new to node js and UI development and i am using this architecture for development . I am stuck to joining 2 table and get the ...

 
lalwanikamaldev profile image
lalwanikamaldev •

Any Idea ?

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pacheco profile image
Thiago Pacheco •

Hello there,
Sorry for the delay, I thought I had answer you already.

You could basically define a comments attribute into your post schema with a reference for this comment schema, like so:

{
 ...your attributes
  comments: [{ type: Schema.Types.ObjectId, ref: 'Comment' }]
});
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Then when you query this post, you can use the populate method from mongoose to retrieve the comments.

Post.
  findOne({ title: 'title' }).
  populate('comments')
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Here is the link with the docs about how you can implement a relationship one-to-many.
mongoosejs.com/docs/populate.html

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pacheco profile image
Thiago Pacheco •

But remember that this is not the same concept of joining as in SQL, in MongoDB you don't have this concept of relationship.
The relationship is defined by code, with your schemas and the extra validations you are supposed to create based on your necessities.

Here is some more information about the key differences between NoSQL and SQL:
mongodb.com/nosql-explained/nosql-...