MongoDB / Mongoose - 通过执行添加更新文档中的数字

I have a mongoDB collection where I store time & costs saved. When the users enter the data for the first time the document kinda looks like this:

我有一个mongoDB集合,可以节省时间和成本。当用户第一次输入数据时,文档有点像这样:

{ "fullName" : "john smith",
  "company" : "xyz",
  "email" : "john.smith@xyz.com",
  "timeSaved" : 50 //this is in minutes
  "moneySaved" : 10 //this is in dollars
}

Now when the user enters the data again I find if a document already exists for this user and if it does I get it.

现在,当用户再次输入数据时,我发现该用户是否已存在文档,如果已存在,我就会得到它。

This time the user entered:

这次用户输入:

Time Saved 55

节省时间55

money Saved 10

钱节省10

I want to add the new values to the existing values. So after the documents shows this:

我想将新值添加到现有值。所以文件显示后:

"timeSaved" : 105 // old 50 + new 55
"moneySaved" : 20 // old 10 + new 10

Whats the best way to achieve this. Is there an inbuilt function in mongodb/mongoose that can help with this.

什么是实现这一目标的最佳方式。 mongodb / mongoose中是否有内置功能可以帮助解决这个问题。

1 个解决方案

#1

You can do this by $inc operator. The $inc operator increments a field by a specified value

您可以通过$ inc运营商执行此操作。 $ inc运算符按字段增加一个字段

For example in your case:

例如在你的情况下:

UserModel.update(
    SomeFindCriteria,
   { $inc: { timeSaved: newTimeSaved, moneySaved: newMoneySaved } }
)

#1