Question

我有以下架构，并尝试更新# coding=utf-8 #! /usr/bin/env python from tablib import Dataset # load data from the tsv with open("./test.csv") as fin: imported_data = Dataset().load(fin.read()) code = input("Please enter Product Code?") quantity = int(input("How many of these do you need?")) # code is uniq find the first index i = imported_data["Code"].index(code) new_qt = int(imported_data[i][3]) - quantity # tuple manipulation, so replace the line, item affection not possible if new_qt >= 0: imported_data[i] = imported_data[i][:-1] + (str(new_qt),) else: imported_data[i] = imported_data[i][:-1] + ("0",) export = imported_data.tsv # newline="" avoid add new lines with open("./test.csv", "w", newline="") as fout: fout.write(export)中的值。

answers.counter

代码：

var postSchema = mongoose.Schema({
  question      : { type: String, required: true },
  answers       : [answerSchema]      
});
var answerSchema = mongoose.Schema({
  answe         : String,
  counter       : { type: counterSchema, ref: 'Counter' }
});
var counterSchema = mongoose.Schema({
  upvotes       : { type: Number, default: 0, min: 0 },
  downvotes     : { type: Number, default: 0, min: 0 }
});

因此对于Post.findOneAndUpdate(where, { '$inc': { 'answers.$.counter.upvotes': 1 } }, {'new': true, runValidators: true }, (err, post) => { if (err) return next(err); console.log('post=' + JSON.stringify(post));，我尝试了以下其他变体：

1）where

2）{ 'answers._id': ObjectId(${req.body.aid}) }

3）{ '_id': ObjectId(${req.body.pid}), 'answers._id': ObjectId(${req.body.aid}) }

我收到以下错误：

{ '_id': ObjectId(${req.body.pid}), 'answers._id': ObjectId(${req.body.aid}) 'answers.counter._id': ObjectId(${req.body.cid}) }

这真让我感到困惑，因为通过mongo console，MongoError: exception: The positional operator did not find the match needed from the query. Unexpanded update: answers.$.counter.upvotes

正确地增加了正确的值，这启动了我的整个路径。

提前感谢任何指示。

Answer 1

事实证明我有一个字符串而不是where的对象。所以对象形式的＃1解决了这个问题：

let where = { '_id': req.body.aid }

以前它是字符串形式（使用$ {}模板）：

let where = `{ 'answers._id': ${req.body.aid} }`

Mongoose位置数组更新

1 个答案: