Question

我正在尝试从Firebase降序获取数据

数据库结构

0G6K7tgHDVXTwPYV5NwhANnWChF2

感觉 -LfP-g3QnO7WmZ3xE8df

   currentFeeling: "Angry"
   reason: "My phone broke"
   timeStamp: 1558435776511

Firebase数据库映像链接 https://user-images.githubusercontent.com/42183565/58200932-5bc15100-7ced-11e9-97f7-6521f229f968.png

这是代码

    func getFeelingsDataFromDatabase(){
        let ref = Database.database().reference()
        let userID = Auth.auth().currentUser?.uid
        ref.child("userData").child(userID!).child("feelings").queryOrdered(byChild: "timeStamp").observeSingleEvent(of: .value, with: { (snapshot) in
            let value = snapshot.value as? [String:AnyObject]
            //print(value)
            for data in value!{
                let feelingsData = FeelingsIndex()
                feelingsData.feelingType = data.value["currentFeeling"] as? String
                feelingsData.reason = data.value["reason"] as? String
                feelingsData.timeStamp = data.value["timeStamp"] as? Double
                self.feelingsList.append(feelingsData)

            }
            DispatchQueue.main.async {
                self.tableView.reloadData()
            }
        }) { (error) in
            print(error.localizedDescription)
        }
    }

我希望数据根据时间戳进行排列。我可以过滤数据吗？每月一次？每年吗？

如何使用“时间戳”以降序从Firebase检索数据？

0 个答案: