Question

我已经简化了以下代码：

var buySchema = new mongoose.Schema({
    userid:String,
    timestamp:Number,
    price:Number
});
var cardSchema = new mongoose.Schema({
    cardid: String,
    buy:[{type:mongoose.Schema.Types.ObjectId, ref:'buy'}],
});

var Card = mongoose.model('cards',cardSchema,'cards');
var Buy = mongoose.model('buy',buySchema,'buy');

Card.findOne({'cardid':cardid}, function(err, card) {

    var newBuy = new Buy({'userid':userid, timestamp:null,price:null});

    newBuy.save(function(err){
      card.buy.addToSet(newBuy._id);
    });

    card.save(function(err,card){
      console.log(card.buy); // card.buy[] has an ObjectId ref
    });

});

Card.findOne({'cardid':cardid}, function(err, card) {
   console.log(card.buy); // !!!!! card.buy[] does not have ObjectId ref !!!!!
});

买[]似乎没有在mongodb中保存ObjectId引用

如果没有ObjectId引用，我怎么能在以后填充卡？他们去哪儿了？我对人口的看法是什么？

Answer 1

你必须为ref添加引号：＆＃39; buy＆＃39;并添加corectly架构。看看mongoosejs docs。

var cardSchema = new mongoose.Schema({
    cardid: String,
    buy:[{type:mongoose.Schema.Types.ObjectId, ref:'buy'}],
});

var Card = mongoose.model('cards',cardSchema);
var Buy = mongoose.model('buy',buySchema);

Answer 2

newBuy.save来电是异步的，因此您card.save来电之前正在进行card.buy.addToSet来电。

因此，请将您的代码部分重新排序为：

newBuy.save(function(err){
  card.buy.addToSet(newBuy._id);
  card.save(function(err,card){
    console.log(card.buy);
  });
});

OR

newBuy.save(function(err){
});

card.buy.addToSet(newBuy._id);
card.save(function(err,card){
  console.log(card.buy);
});

Answer 3

因此，在保存孩子时，你必须将父母保存在孩子保存的回调中，如下所示：

newBuy.save(function(err){
  card.buy.addToSet(newBuy._id);
  card.save(function(err,card){
    console.log(card.buy); // card.buy[] has an ObjectId ref & is actually saved to db
  });
});

Mongoose Population ObjectId ref正在消失？

3 个答案: