推入 mongodb 中的文档数组答案

【问题标题】：Push into an array of documents in mongodb推入 mongodb 中的文档数组
【发布时间】：2018-12-11 07:00:39
【问题描述】：

使用哪个运算符将新问题推送到问题数组中？我有以下格式的文档。如果给定了 chapterId 和 subchapterId，则使用哪个 mongo db 运算符将新问题插入问题数组中前进。

例如，我想在 subchapterId "1" 中插入一个新问题。

  {

    "chapterId": "38",
    "subChapter": [
      {

        "subchapterId": "1",
        "questions": [
          {

            "title": "Either his however modern. Stop central owner color type out. Interview five beyond interesting type suddenly.",

          },
          {

            "title": "Amount himself foreign color moment gun together sit. Deal race range heart despite several. Rather activity eat dinner save mission western. Civil past public enter four then.",

          },
          {

            "title": "Four former operation. Class continue away treatment.\nResponsibility condition dinner realize everything. Sign scene order quality yet. Within sing statement skill popular southern whole."

          },
          {

            "title": "Where of coach nature ask page allow.\nType exist hotel time. Central site policy everyone safe. Official administration family somebody.",

          },
          {

            "title": "Necessary dark these much region. Form sometimes seek. Future according detail piece section.\nNear everything admit. Senior Republican draw as expert market.",

          }
        ]
      },
      {

        "subchapterId": "2",
        "questions": [
          {

            "title": "Audience still use group. Yourself building police. Play imagine serious reality population reach.\nHerself without member must think concern window finish."

          },


          {

            "title": "Rule trip manage still. Imagine religious above race something successful.\nOnce base American series. Low page quite allow. Customer maybe base leave way under blood.",

          },
          {

            "title": "Church audience anyone garden. Federal when individual style.Value billion morning need box whether. Coach traditional cold each us truth.",

          }
        ]
      }
    ]
  }

【问题讨论】：

认为这可能会有所帮助stackoverflow.com/questions/13987365/…

标签： javascript arrays json mongodb mongoose

【解决方案1】：

你可以试试这个

const title = "this is the new question"

db.collection.update(
  { "subChapter.subchapterId": "1" },
  { "$push": { "subChapter.$.questions": { title } }}
)

【讨论】：

【解决方案2】：

您可以将 $push 与更新一起使用

示例代码适用于 chapterId:38 和 subchapterId:1

db.collection_name.update({ "chapterId":"38", "subChapter.subchapterId": "1" }, { $push: { "subChapter.$.questions":{'title':'Newly added record'} }})

【讨论】：

【解决方案3】：

使用$addToSet 避免更新时对象数组中的重复项

db.yourcollectionName.update({        
  "subChapter.subchapterId" :"1"
},{$addToSet:{"subChapter.$.questions":{title:"updated Object"}}})

【讨论】：