Firestore按日期和时间分别查询 [英] Firestore query by dates and times separately

问题描述

如何按特定的日期和时间范围查询文档? IE.我想按特定日期范围(01-01-2019-31-01-2019)查询文档，并且从这些日期开始仅查询上午10点至下午12点的文档.

How do I query my documents by specific date and time range? Ie. I want to query documents by specific date range (01-01-2019 - 31-01-2019) and from those dates only the documents which are made in 10am to 12pm.

它会是这样的:

let ref = db.collection('events')

// Query by date range
ref = ref
  .where('created', '>=', new Date(2019, 1, 1, 10, 0, 0, 0))
  .where('created', '<=', new Date(2019, 1, 1, 12, 0, 0, 0))

// Query by time range in each date
ref = ref
  .where('created', '>=', *START TIME = 10pm*)
  .where('created', '<=', *END TIME = 12pm*)

所以问题是我每天如何过滤查询的小时和分钟?希望你理解我在这里要问的问题！如有需要，我将更新问题.

So the question is how do I filter hours and minutes every day I queried? Hopefully you understand what I'm asking here! I'll update the question if needed.

更新 数据库结构正在关注

Update Database sturcture is following

/events/{单个事件文档}:

{
  cafeId: String,
  created: Firestore timestamp // ex. February 2, 2019 at 10:16:00 AM UTC+2
  discount: Number,
  eventId: Number,
  productCount: Number,
  keywords: Array,
  products: Map,
  payment: Map,
  returned: Number,
  total: Number
}

当我在客户端创建此文件时，它将转换为:

And when I get this in the client created will transform to:

{ _seconds: Number, _nanoseconds: 0 }

推荐答案

如果要使用标准" where()方法，则可能必须对前端的第二个过滤进行第二次过滤，以

If you want to use "standard" where() methods, you'll probably have to do the second filtering on your front end, from the results received with

ref = ref
  .where('created', '>=', new Date(2019, 1, 1, 10, 0, 0, 0))
  .where('created', '<=', new Date(2019, 3, 1, 12, 0, 0, 0))

---

另一种方法是在一个额外的字段(例如createdText)中以自定义格式(例如YYYYMMDDHHMM)将日期/时间值存储为小时(例如HH)以24小时格式

---

Another approach would be to store, in an extra field (e.g. createdText), your date/time value with a custom format, like for example YYYYMMDDHHMM, with a 24 hours format for the hours (i.e. HH).

这样，文档将被正确排序，并且您只能使用一个where进行查询，如下所示:

This way the document will be correctly sorted and you can query with only one where, as follows:

ref = ref
  .where('createdText', '>=', '201902031000')
  .where('createdText', '<=', '201902041200')

在NoSQL数据库中复制数据非常普遍，尤其是允许根据您的业务需求进行查询.

It is quite common to duplicate the data in an NoSQL database, in particular to allow querying according to your business needs.

这篇关于Firestore按日期和时间分别查询的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！