Question

我在这里遇到挑战，我试图从同一个集合中的另一个子文档填充子文档。这可能吗？下面是我的示例模式

var chapter = new Schema({
  title:String,
  startPage:Number,
  endPage:Number
});


var keyPoint = new Schema({
  text:String,
  mentionInChapter:[{
      type: Schema.ObjectId,
      ref: 'chapter'}]
});


var Book = new Schema({
   title:String,
   author:String,
   chapters:[chapter],
   keyPoints:[keypoint]
});

我在下面尝试过，它没有在keyPoints数组中填充chapterId。

Book.findById（ID）.populate（＆＃39;章＆＃39）。EXEC（功能（ERR，DOC）{ 如果（！ERR）的console.log（DOC）; }）;

有没有办法实现这一点，以便我检索的Book文档中填充了所有详细信息？

Answer 1

您可以尝试使用Model.populate方法，如下所示：

var chapter = new Schema({
  title:String,
  startPage:Number,
  endPage:Number
});

var keyPoint = new Schema({
  text:String,
  mentionInChapter:[{type: Schema.ObjectId, ref: 'chapter'}]
});

var Book = new Schema({
   title:String,
   author:String,
   chapters:[chapter],
   keyPoints:[keyPoint]
});

Book.findById(id)
   .lean()
   .populate('chapters keyPoints')
   .exec(function (err, docs) {
      if (err) throw err;

      Book.populate(docs, {path: 'keyPoints.mentionInChapter'}, function (err, book) {
         if (err) throw err;

         console.log(book);
      });
   });

更新：版本2：

var chapter = new Schema({
  title:String,
  startPage:Number,
  endPage:Number
});

var keyPoint = new Schema({
  text:String,
  mentionInChapter:[{type: Schema.ObjectId, ref: 'chapter'}]
});

var Book = new Schema({
   title:String,
   author:String,
   chapters:[chapter],
   keyPoints:[keyPoint]
});

Book.findById(id).exec(function (err, doc) {
   if (err) throw err;

   Book.populate(doc, {path: 'keyPoints.mentionInChapter'}, function (err, book) {
      if (err) throw err;

      console.log(book);
   });
});

Mongoose从另一个子文档填充子文档，其中两个子文档都是主文档

1 个答案: