Mongo 在双嵌套数组中更新

Question

我有一个看起来像这样的 mongo 集合

db.users.find().pretty()
{
    "_id" : ObjectId("57c3d5b3d364e624b4470dfb"),
    "fullname" : "tim",
    "username" : "tim",
    "email" : "tim@gmail.com",
    "password" : "$2a$10$.Z9CnK4oKrC/CujDKxT6YutohQkHbAANUoAHTXQp.73KfYWrm5dY2",
    "workout" : [
        {
            "workoutId" : "Bkb6HIWs",
            "workoutname" : "chest day",
            "BodyTarget" : "Chest",
            "date" : "Monday, August 29th, 2016, 2:27:04 AM",
            "exercises" : [
                {
                    "exerciseId" : "Bym88LZi",
                    "exercise" : "bench press",
                    "date" : "Monday, August 29th, 2016, 2:29:30 AM"
                },
                {
                    "exerciseId" : "ByU8II-s",
                    "exercise" : "flys",
                    "date" : "Monday, August 29th, 2016, 2:29:34 AM"
                }
            ]
        },
        {
            "workoutId" : "Bk_TrI-o",
            "workoutname" : "Back day",
            "BodyTarget" : "Back",
            "date" : "Monday, August 29th, 2016, 2:27:12 AM"
        }
    ]
}

所以我最终希望它看起来像这样

db.users.find().pretty()
{
    "_id" : ObjectId("57c3d5b3d364e624b4470dfb"),`enter code here`
    "fullname" : "tim",
    "username" : "tim",
    "email" : "tim@gmail.com",
    "password" : "$2a$10$.Z9CnK4oKrC/CujDKxT6YutohQkHbAANUoAHTXQp.73KfYWrm5dY2",
    "workout" : [
        {
            "workoutId" : "Bkb6HIWs",
            "workoutname" : "chest day",
            "BodyTarget" : "Chest",
            "date" : "Monday, August 29th, 2016, 2:27:04 AM",
            "exercises" : [
                {
                    "exerciseId" : "Bym88LZi",
                    "exercise" : "bench press",
                    "date" : "Monday, August 29th, 2016, 2:29:30 AM",
                    "stats" : [
                          {
                            "reps: '5',
                            "weight":'105'
                          }
                },
                {
                    "exerciseId" : "ByU8II-s",
                    "exercise" : "flys",
                    "date" : "Monday, August 29th, 2016, 2:29:34 AM"
                }
            ]
        },
        {
            "workoutId" : "Bk_TrI-o",
            "workoutname" : "Back day",
            "BodyTarget" : "Back",
            "date" : "Monday, August 29th, 2016, 2:27:12 AM"
        }
    ]
}

我想将 stats 数组添加到当前的练习数组中。我在使用双嵌套数组的点表示法时遇到问题

我试过这个

db.users.update({
  'email': 'jeffreyyourman@gmail.com', "workout.workoutId": "Bkb6HIWs" ,"workout.exercises.exerciseId":"ByU8II-s"
},
{
  $push: {
          "workout.0.exercises.$.stats": {"sets":"sets", "reps":"reps"}}})

这实际上有效，但总是会推送到第一个嵌套的练习对象。

现在如果我这样做...

db.users.update({
  'email': 'jeffreyyourman@gmail.com', "workout.workoutId": "Bkb6HIWs" ,"workout.exercises.exerciseId":"ByU8II-s"
},
{
  $push: {
          "workout.0.exercises.1.stats": {"sets":"sets", "reps":"reps"}}})

并将 $ 替换为 1 它将推送到第二个练习数组，这显然是我想要的。但是我正在建立一个网站，所以我显然不能对其进行硬编码。我需要使用 $ 但它似乎没有让它通过第一个练习对象。

任何帮助我将不胜感激！

Answer 1

现在（MongoDB >=3.6）有一种方法可以使用arrayFilters和$[identifier]来做到这一点。

下面的示例使用 mongoose 并将一个项目添加到双嵌套数组内的数组中。一个很好的文章，解释这是在这里。

  const blogPost = await BlogPost.create({
    title    : 'A Node.js Perspective on MongoDB 3.6: Array Filters',
    comments : [
      { author : 'Foo', text : 'This is awesome!', replies : { name : 'George', seenBy : ['Pacey'] } },
      { author : 'Bar', text : 'Where are the upgrade docs?', replies : { name : 'John', seenBy : ['Jenny'] } }
    ]
  });

  const updatedPost = await BlogPost.findOneAndUpdate({ _id : blogPost._id }, {
    $addToSet : {
      'comments.$[comment].replies.$[reply].seenBy' : 'Jenny'
    }
  }, {
    arrayFilters : [{ 'comment.author' : 'Foo' }, { 'reply.name' : 'George' }],
    new          : true
  });

  console.log(updatedPost.comments[0].replies);