根据“时间"从MongoDB集合中删除文档.日期字段的 [英] Remove documents from a MongoDB collection based on "time" of a Date field

问题描述

我有一个集合，该集合存储具有以下结构的文档:

I have a collection which stores documents with the following structure:

{ 
    "_id" : NumberLong(-6225637853094968071), 
    "Id" : "1585534", 
    "Type" : NumberInt(42), 
    "InDate" : ISODate("2017-10-05T18:30:00.000+0000"), 
}
{ 
    "_id" : NumberLong(-622563784353458071), 
    "Id" : "15832422", 
    "Type" : NumberInt(42), 
    "InDate" : ISODate("2017-10-06T00:00:00.000+0000"), 
}

我要删除所有带有特定"Id"和"Type"的文档，其中"InDate"字段的时间为18:30:00.000+0000.我尝试使用此查询:

I want to delete all documents with a particular "Id" and "Type" where the "InDate" field has time 18:30:00.000+0000. I tried using this query:

 db.collection.remove({
"ChannelType": NumberInt(28),
"HotelId": "1585534",
"CheckInDate": /$18:30:00.000+0000/
})

但是它不起作用.该怎么做?

but it doesnt work. How to do this?

推荐答案

正则表达式不适用于非字符串的内容.实际上，没有简单的方法可以通过普通查询表达式中的时间值来选择BSON Date.

A Regular Expression will not work on something that is not a string. There actually is no simple way of selecting a BSON Date by purely it's time value in a regular query expression.

为此，您需要提供 $where 条件，并具有附加的逻辑以仅在日期值的时间部分进行匹配.

In order to do this you would supply a $where condition with the additional logic to match on just the time portion of the date value.

根据问题中实际提供的数据:

Based on the data actually supplied in the question:

db.getCollection('collection').remove({
  "Id": "1585534",
  "Type": NumberInt(42),
  "$where": function() {
    return this.InDate.getUTCHours() === 18
      && this.InDate.getUTCMinutes() === 30
  }
})

当然，这只是提供的数据中的第一个文档，尽管它实际上只是由"Id"标识的，因为该值在两者之间是唯一的.

Which is of course just the first document in the provided data, even though it's really just identified by "Id" anyway since that value is unique between the two.

.getUTCHours() 和 .getUTCMinutes() 是JavaScript Date 对象方法，是在 $where $where 表达式.

The .getUTCHours() and .getUTCMinutes() are JavaScript Date object methods, which is how a BSON Date is expressed when used within a $where expression.

通常，MongoDB 3.6(在撰写本文时即将推出)比

Trivially, MongoDB 3.6 ( upcoming as of writing ) allows a more efficient form than $where in aggregation expressions:

db.getCollection('collection').aggregate([
  { "$match": {
    "Id": "1585534",
    "Type": NumberInt(42),
    "$expr": {
      "$and": [
        { "$eq": [{ "$hour": "$InDate" }, 18 ] },
        { "$eq": [{ "$minute": "$InDate" }, 30] } 
      ] 
    }   
  }}
])

但是，此类表达式不能直接与 .remove() 或 .deleteMany() ，但是 $where 表达式可以.

However such expressions cannot be used directly with methods such as .remove() or .deleteMany(), but $where expressions can.

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