Mongoose Association query

// 
let articleSchema = new Schema({
    title: String,
    content: String
)}
// 
let commentSchema = new Schema({
    title: String,
    content: String,
    article: { type: Schema.Types.ObjectId, ref: "Article" }
)}
var Article = mongoose.model("Article", articleSchema );
var Comment = mongoose.model("Comment", commentSchema );

when I want to get the list of articles again, I use the article _ id to get the comments under the article. I have thought for a long time that "populate" can only retrieve the article from the comments. What should I do? it is impossible to write the ref of n comments in the article. It doesn"t feel realistic. Can you only get to the list of articles and go through each article again? Solve

Mongodb
Mar.02,2021

article can store a comment _ id array, so you can populate comments

. 
let articleSchema = new Schema({
    title: String,
    content: String,
    comments:[{
    type: Schema.Types.ObjectId, ref: 'Comment'
    }]
)}

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