如果文档_id已经存在,如何将数组元素推到数组中,如果_id不存在,如何创建新文档? [英] How to push array elements to an array if _id of documents already exists and create new document if _id doesn't exist?
问题描述
我正在使用Node.js
,mongoose
,mongodb
,express
和angular
.
我在猫鼬模型中保存了对调查的答复.许多人会针对特定调查提交答复.当第一个人提交调查问卷答复时,我想为该调查问卷创建一个新文档.当第二个,第三个...等人提交针对同一调查的答复时,我只想将数组元素添加到以下架构中的答复数组中.
I am using Node.js
, mongoose
, mongodb
, express
and angular
.
I am saving replies for a survey in a mongoose model. Many people will submit replies for a particular survey. When the first person submits a reply for a survey, I want to create a new document for that survey. When the second, third.... so on people submit replies for the same survey, I want to add array elements only to the replies array in the following schema.
当第一个人对新调查提交答复时,我想为新调查创建新文档.我该怎么用猫鼬呢?
And when the first person submits a reply for a new survey I want to create a new document for the new survey. How can I do this in mongoose?
我在 Mongoose.js中发现了类似的问题:如何实现创建或更新?. 但是,如果找到了_id,我想在这里将新回复推送到下一个回复数组索引[],否则请创建一个新文档
猫鼬模型:
var mongoose = require("mongoose");
var Schema = mongoose.Schema;
var MCQReplySchema = new Schema({
_id : String,
surveyname: String,
replies :[{
replierId : String,
answers : [{
questionId : String,
answer : String
}]
}]
});
module.exports=mongoose.model('MCQReply',MCQReplySchema);
将数据保存到数据库:
router.post("/saveMCQAnswer", function(req, res) {
new MCQReply({
_id : '123',
surveyname: 'sample',
replies :[{
replierId : 'R001',
answers : [{
questionId : 'A001',
answer : 'answer'
}]
}]
}).save(function(err, doc){
if(err) res.json(err);
else
req.flash('success_msg', 'User registered to Database');
res.redirect("/");
});
});
推荐答案
伪未经测试的代码.
MCQReply.findOne({_id : the id}, function(err,doc){
if(err) console.log(err);
// if the survey isn't there `doc` will be null then do your save
if(!doc){
new MCQReply({
_id : '123',
surveyname: 'sample',
replies :[{
replierId : 'R001',
answers : [{
questionId : 'A001',
answer : 'answer'
}]
}]
}).save(function(err, doc){
if(err) res.json(err);
else
req.flash('success_msg', 'User registered to Database');
res.redirect("/");
});
}else(doc){
//you get mongoose document
doc.replies.push({replierId : "R001", answer : [{questionId : "A001" ... whatever else you want}]})
//dont forget to save
doc.save(do error check)
}
})
不知道这是否行得通,但是如果您在保存_id时遇到麻烦,请尝试使用Schema()
Don't know if this will work but if your having trouble just saving the _id try this for Schema()
var MCQReplySchema = new Schema({
_id : String,
surveyname: String,
replies :[{
replierId : String,
answers : [{
questionId : String,
answer : String
}]
}]
}, {strict : false});
如果{strict :false}
不起作用
尝试{strict : false, _id :false}
或仅_id : false
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