Mongoose

Question

集合架构

const notificationsSchema = new mongoose.Schema({
  content: {
    type: String,
    required: true,
    maxlength: 1000
  },
  recipient: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'User',
    required: true
  }
 }
});

对应的数据库条目

{
  "_id" : ObjectId("607c1ebc3c2e16b610d74464"),
  "content" : "Test Content",
  "recipient" : "607c1e2c0bb25343e53abf45" <--- Existing _id of a user
}

正在尝试按收件人字段查找

deleteUser: combineResolvers(async (_, { id }) => {
      try {
        const user = await User.findById(id);
        console.log(user.id); <-- returns 607c1e2c0bb25343e53abf45
        
        // Option 1
        const notification = await Notification.findOne({ recipient: user.id }); 
        console.log(notification); <-- returns null

        // Option 2
        const userId = mongoose.Types.ObjectId(user.id);
        const notificationObjectId = await Notification.findOne({ recipient: userId }); 
        console.log(notificationObjectId); <-- returns null

        // Working alternative
        const notificationAlternative = await Notification.findOne({ content: "Test Content" });
        console.log(notificationAlternative); <-- returns the correct document

        return true;
      } catch (error) {
        throw error;
      }
    })

澄清一下，我不是要通过收件人字段查找用户，而是要通过收件人字段查找通知文档。为什么我无法通过收件人 ID 检索文档？我错过了什么？

Answer 1

错误很可能是因为执行时数据类型不同const notification = await Notification.findOne({ recipient: user.id }); 。检查 user.id 的数据类型，需要转换为字符串 user.id.toString()

Mongoose - 通过引用字段 _id 查找

Mongoose - find by referenced field _id

mongodb

mongodb-query

objectid