Question

我试图访问嵌套在多个文档数组中的某个值。我已尝试各种语法来显示但无法找到方法。如何使用.find（）获取值“aboveAve”？我需要进入注册 - ＆gt;进入 - ＆gt; GameStats

这是文档结构：

{
  _id: ObjectId("5a665852f5b2abdbcdd190be"),
  Name: "Beat Your Average",
  MinPlayers: NumberLong("0"),
  MaxPlayers: NumberLong("1"),
  VisibleStartDateTime: ISODate("2018-01-22T20:27:40.497Z"),
  StartDateTime: "2018-01-22T20:27:40.497Z",
  VisibleEndDateTime: ISODate("2018-02-08T23:55:40.497Z"),
  EndDateTime: "2018-02-08T23:55:40.497Z",
  PayoutScale: NumberLong("20171004"),
  PrizeFund: NumberLong("10000"),
  EntryFee: NumberLong("500"),
  Rake: NumberLong("500"),
  Completed: true,
  Live: false,
      Registrations: [
      {
          UserId: NumberLong("231704"),
          ContestId: "5a665852f5b2abdbcdd190be",
          RegistrationDateTime: ISODate("2018-01-22T21:32:02.900Z"),
          TimezoneOffset: NumberLong("300"),
          PromisedBowlDate: "2018-01-22",
          Entry: {
            UserId: NumberLong("231704"),
            TimezoneOffset: NumberLong("300"),
            Games: [
              NumberLong("125"),
              NumberLong("125"),
              NumberLong("135")
            ],
            Pinfall: NumberLong("385"),
            SeriesScore: NumberLong("385"),
            Photos: [
              "/home/rtb/uploads/a5cc578a3e4384ca4e7490e7b0af2fd19a99c6b6d09eab5fee2f1c45707fe38b/1516656862357_1c67eba6_3dd2_4e5a_9142_bc27602d64a6"
            ],
            EntryDateTime: ISODate("2018-01-22T21:34:22.387Z"),
            Average: NumberLong("95"),
            EntryId: "29ba83cc-5ae1-49cf-b74f-c15b8bb17808",
            Disqualified: false,
            CenterId: NumberLong("2963"),
            LeagueId: NumberLong("-1"),
            Lane: NumberLong("6"),
            Position: NumberLong("5"),
            DisplayName: "JESS B",
            RegistrationDateTime: ISODate("2018-01-22T21:32:02.900Z"),
            Status: NumberLong("1"),
            WinningsTotal: NumberLong("15"),
            BonusAmount: NumberLong("35"),
            TripleWin: "Tier 1",
            Payout: NumberLong("5000"),
            GameStats: [
              {
                game: "Game 1",
                pinfall: NumberLong("125"),
                aboveAve: NumberLong("30"),
                prize: "$5"
              },

Answer 1

如果要返回包含aboveAve字段的所有元素，则必须使用$exists。由于您只想返回aboveAve的值，因此您还需要指定要包含在投影中的字段。

db.collection.find({ "Registrations": { "Entry.GameStats": {"aboveAve": {$exists: true, $ne: null}}}}, {"aboveAve": 1, "_id":0 })

在mongodb集合中深入挖掘价值

1 个答案: