按时间戳排序，在不同的字段Swift Firestore上使用范围过滤器

Question

我之前已经问过这个问题但尚未找到有效的解决方案。 我想要的是获得一个年龄范围内的用户列表，并按照“创建过程”排序。时间戳，但由于生日＆＃39;范围过滤第一个订单必须在生日＆＃39;字段。

这是我的疑问：

database.collection("users")
    .whereField("birthday", isGreaterThan: exploreSettings.upperAgeDate)
    .whereField("birthday", isLessThan: exploreSettings.lowerAgeDate)
    .whereField("isHidden", isEqualTo: false)
    .order(by: "birthday", descending: true)
    .order(by: "createdAt", descending: true)
    .limit(to: 8)
    .start(afterDocument: lastSnapshot)
    .getDocuments {...}

这就是它将返回的内容

[
    ["name": "John", "age": 21, "createdAt": 2005],
    ["name": "Jane", "age": 22, "createdAt": 2003],
    ["name": "Adam", "age": 23, "createdAt": 2004],
    ["name": "Karl", "age": 24, "createdAt": 2001],
    ["name": "Mila", "age": 25, "createdAt": 2002],
]

我希望它返回

[
    ["name": "Karl", "age": 24, "createdAt": 2001],
    ["name": "Mila", "age": 25, "createdAt": 2002],
    ["name": "Jane", "age": 22, "createdAt": 2003],
    ["name": "Adam", "age": 23, "createdAt": 2004],
    ["name": "John", "age": 21, "createdAt": 2005],
]

有些人建议我以某种方式将生日和时间戳合并到一个字段中，但我知道我应该如何做到这一点

Answer 1

尝试使用此功能：

      let arrResponse = [
        ["name": "John", "age": 21, "createdAt": 2005],
        ["name": "Jane", "age": 22, "createdAt": 2003],
        ["name": "Adam", "age": 23, "createdAt": 2004],
        ["name": "Karl", "age": 24, "createdAt": 2001],
        ["name": "Mila", "age": 25, "createdAt": 2002],
        ]


    let descriptor : NSSortDescriptor = NSSortDescriptor(key: "createdAt", ascending: true)

    let sortedResult = (arrResponse as NSArray).sortedArray(using: [descriptor])

    print(sortedResult)

输出是这样的：