检查文档是否已经存在，如果是，则进行更新，否则创建新的-猫鼬 [英] Check if document already exists and if yes then update, otherwise create new - Mongoose

问题描述

我有一个应用程序，试图检查是否存在具有用户ID的文档，如果存在，则使用请求中发送的数据更新现有文档(如果不存在)，然后创建一个新文档.

I have app where I am trying to check whether a document with the users ID already exists, if yes then update the existing one with the data sent in the request if it does not exist then create a new document.

到目前为止，我已经这样做:

Bio.findOne({userID: req.body.userID}, function(err, bio) {
        if (err) {
            console.log("The error while updating colleciton is " + err);
        }
        // if already exists then update it
        if (bio) {
            console.log("Bio document for user already exists!");
            bio.userBios = {
                $push: {
                    background: req.body.userBios.background,
                    experience: req.body.userBios.experience,
                    skills: req.body.userBios.skills,
                    bioForSector: req.body.userBios.bioForSector
                }
            }
            bio.save(function(err) {
                if (err)
                    throw err
                return (null, bio)
            })
        }
        //if does not exist then create new 
        if (!bio) {
            console.log("Bio document for user does NOT exist! creating new");
            var bio = new Bio();

            bio.firstName = req.body.firstName;
            bio.lastName = req.body.lastName;
            bio.jobTitle = req.body.jobTitle;
            bio.userID = req.body.userID;
            bio.userBios = {
                background: req.body.userBios.background,
                experience: req.body.userBios.experience,
                skills: req.body.userBios.skills,
                bioForSector: req.body.userBios.bioForSector
            };

            // save the bio
            bio.save(function(err) {
                if (err)
                    throw err;
                return (null, bio);
            });
        }
    });

问题:

我可以成功创建一个新文档，但是当我尝试对其进行更新时，它将覆盖整个userBios数组，而不是对其进行更新.

I can successfully create a new document but when I try to update it, it overwrites the whole userBios array rather then updating it.

我的文档架构:

// define the schema for our bios model
 var biosSchema = mongoose.Schema({
     firstName: String,
     lastName: String,
     jobTitle: String,
     userID: String,
     userBios: [{bioForSector: String, background: String, skills: [String], experience: {}}]
     });

我做错了什么?有人可以帮忙吗?会非常感激的！

What am I doing wrong? Can anyone help? it'll be much appreciated!

推荐答案

就像Alexander Mac在评论中说的那样，您自己重写了数组.如果该文档存在，请尝试:

Like Alexander Mac says in the comments, you are overriding the array yourself. If the document exists, try:

if (bio) {
    console.log("Bio document for user already exists!");
    bio.userBios.push({
        background: req.body.userBios.background,
        experience: req.body.userBios.experience,
        skills: req.body.userBios.skills,
        bioForSector: req.body.userBios.bioForSector
    });
    bio.save(function(err) {
        if (err)
            throw err
        return (null, bio)
    });
}

通过这种方式，您可以将其真正推送到现有阵列中，而不是创建一个新阵列.

This way you really push it in an existing array instead of creating a new one.

这篇关于检查文档是否已经存在，如果是，则进行更新，否则创建新的-猫鼬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！