跨文档的数组元素上的MongoDB唯一索引(不跨嵌套文档) [英] MongoDB Unique Index on array element across documents (not across nested document)

问题描述

我有一个架构如下:

Schema = mongoose.Schema    
User= new Schema
    { name: String,
     phones: [
    {
      confirmed: {
        type: Boolean,
        default: false
      },
      number: {
        type: String,
        unique: true
      }
  ]}  

这应该不允许使用相同的电话号码创建 2 个文档.我知道索引在数组元素中不能是唯一的，所以我可以在嵌套文档中有 1 个具有 2 个相同数字的文档，但我不希望 2 个文档具有相同的数字.未创建索引.我检查了可能不允许创建索引的现有重复文档，但没有.我尝试使用

This was supposed not to allow creation of 2 documents with same phone number. I understand that the index cant be unique across array elements so i am fine of having 1 document with 2 same numbers in the nested document but i dont want 2 documents to have same number. The index is not being created. I checked for existing duplicate documents that might be not allowing the index to be created but there is not. I tried creating the index in atlas with

{ "phones.number": 1 }, {unique:true}

{ "phones.number": 1 }, {unique:true}

它根本没有创建它

推荐答案

为此，您需要更改一些内容.

To do this you need to change a few things.

首先，您的架构必须是这样的 index:

First of all, your schema has to be an index like this:

number: {
  type: String,
  index: true, // <-- This line
  unique: true
}

并且，在您的连接选项中添加 useCreateIndex: true.例如，我有:

And, in your conections option add useCreateIndex: true. For example, I have:

const mongooseOpts = {
    useNewUrlParser: true,
    useFindAndModify: false,
    useUnifiedTopology: true,
    useCreateIndex: true //<-- This line
};

await mongoose.connect(uri, mongooseOpts);

然后，当您尝试添加重复的电话号码时，将引发错误.

Then, when you try to add a duplicate number phone an error will be thrown.

BulkWriteError: E11000 重复键错误 dup key: { : 1";}

BulkWriteError: E11000 duplicate key error dup key: { : "1" }

通过这两个步骤，如果也不起作用，请尝试删除collection并重新创建.

With these two steps, if also didn't work, try removing the collection and creating again.

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