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Nodejs Mongo insert into subdocument - dynamic fieldname
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Closed 8 years ago.
I've run into a situation where I need to dynamically update the value of a field in a subdocument. The field may or may not already exist. If it doesn't exist, I'd like mongo to create it.
Here's an example document that would be found in my Teams collection, which is used to store members of any given team:
{
_id : ObjectId('JKS78678923SDFD678'),
name : "Bob Lawblaw",
status : "admin",
options : {
one : "One",
two : "Two"
}
}
And here's the query I'm using (I'm using mongojs as my mongo client) to try and update (or create) a value in the options subdocument:
var projectID = 'JKS78678923SDFD678';
var key = 'Three';
var value = 'Three';
Teams.findAndModify({
query: {
projectID:mongojs.ObjectId(projectID)
},
update: {
$set : { options[key] : value }
},
upsert: true,
multi: false,
new: true
},
function(error, result, lastErrorObject){
console.log(result);
});
But I can't get it to 'upsert' the value.
I also found this similar question, but that method didn't work either:
Nodejs Mongo insert into subdocument - dynamic fieldname
Thanks in advance for any help.
Figured this out.
Essentially, you need to construct a 'placeholder' object of the sub-document you're trying to update before running the query, like so:
var projectID = 'JKS78678923SDFD678';
var key = 'Three';
var value = 'Three';
var placeholder = {};
placeholder['options.' + key] = value;
Teams.findAndModify({
query: {
projectID:mongojs.ObjectId(projectID)
},
update: {
$set : placeholder
},
upsert: true,
multi: false,
new: true
},
function(error, result, lastErrorObject){
console.log(result);
});
This updates any fields that already exist, and creates the field/value pair if it didn't already exist.
Related
I'd like to configure an upsert. If _id already exists on my object, it recognizes that and updates the match. If _id doesn't exist, it should insert the new document and generate an _id. I'd expect { _id: obj._id } to work, but that overrides the auto-generation of _id. The document appears with _id: null. Is there a filter that would work for this? Do I need to route to insert/update in-code?
Edit: add query.
collection.updateOne(
{ _id: entity._id },
{ $set: entity },
{ upsert: true }
)
Edit: try delete.
Even when I delete the property, no luck.
const upsertTest = (collection) => {
const entity = { date: new Date() };
console.log(entity);
// { date: 2019-11-19T22:16:00.914Z }
const _id = entity._id;
delete entity._id;
console.log(entity);
// { date: 2019-11-19T22:16:00.914Z }
collection.updateOne(
{ _id: _id },
{ $set: entity },
{ upsert: true }
);
console.log(entity);
// { date: 2019-11-19T22:16:00.914Z }
}
But the new document is this:
screenshot of new document
You have to use $setOnInsert to Insert _id
let ObjectID = require('mongodb').ObjectID;
collection.updateOne(
{ _id: entity._id },
{ $set: entity,$setOnInsert:{_id:new ObjectID()}},
{ upsert: true }
)
As the name suggests it will set the _id on insert
If you are using mongodb then new ObjectID() should work,
If its mongoose then you can use mongoose.Types.ObjectId() to generate new ObjectID
Well I Found your Issue
Changed in version 3.0: When you execute an update() with upsert: true and the query matches no existing document, MongoDB will refuse to insert a new document if the query specifies conditions on the _id field.
So in a nutshell you cannot insert a new doc using upsert:true if your query is using _id, Reference
First of all, the _id property WILL always exist, whether you set it yourself or let it auto-generate. So there's no need to check if it exists.
The syntax for upsert is as follows:
db.collection.update({
_id: 'the id you want to check for' // can put any valid 'find' query here
}, {
$set: {
foo: 'bar',
biz: 'baz'
}
}, {
upsert: true
});
If a document with the given _id exists, it will be updated with the $set object. If it does not exist, a new one will be created with the properties of the $set object. If _id is not specified in the $set object, a new _id value will be auto-generated, or will keep using the existing _id value.
The key here is using $set, rather than putting the object right in there. Using set will merge and replace the properties. Without $set it will replace the entire document, removing any unset properties.
Edit: Now seeing the actual query you made, I would suggest you delete the _id property from the entity before setting it. This will make sure it is left alone.
const _id = entity._id;
delete entity._id;
// now do your query using the new `_id` value for the ID.
From our comments you mentioned you were using the local database. The local database allows _id to be null. Using any other DB should fix your issue.
If the entity._id is null then it will create a doc with _id null, We can solve this issue by adding Types.ObjectId(). If the _id doesn't exist then it will create a new document with the proper _id. otherwise, it will update the existing document.
const { Types } = require("mongoose")
collection.updateOne({ _id: Types.ObjectId(entity._id) },{ $set: entity },{ upsert: true})
I'm attempting to write a find query where one of the keys is unknown at the time the query is run, for example on the following document I'm interested in returning the document if "setup" is true:
{
"a": {
"randomstringhere": {
"setup": true
}
}
}
However I can't work how to wildcard the "randomstringhere" field as it changes for each document in the collection.
Can somebody help?
There is not much you can do with that. But you can modify your collection schema like
{
"a": [
{
"keyName": "randomstringhere",
"setup": true
},
//...
]
}
you can than write query to look
{
'a' : { $elemMatch: { setup: true } ,
}
You can't do this with a single query, as with the current design you would need a mechanism to get all the random keys that you need and then assemble the query document that uses the $or operator in the event that you get a list of variable key name.
The first part of your operation is possible using Map-Reduce. The following mapreduce operation will populate a separate collection called collectionKeys with all the random keys as the _id values:
mr = db.runCommand({
"mapreduce": "collection",
"map" : function() {
for (var key in this.a) { emit(key, null); }
},
"reduce" : function() { },
"out": "collectionKeys"
})
To get a list of all the random keys, run distinct on the resulting collection:
db[mr.result].distinct("_id")
Example Ouput
["randomstring_1", "randomstring_2", "randomstring_3", "randomstring_4", ...]
Now given the list above, you can assemble your query by creating an object that will have its properties set within a loop. Normally your query document will have this structure:
var query = {
"$or": [
{ "a.randomstring_1.setup": true },
{ "a.randomstring_2.setup": true },
{ "a.randomstring_3.setup": true }
]
};
which you can then use in your query:
db.collection.find(query)
So using the above list of subdocument keys, you can dynamically construct the above using JavaScript's map() method:
mr = db.runCommand({
"mapreduce": "collection", // your collection name
"map" : function() { // map function
for (var key in this.a) { emit(key, null); }
},
"reduce" : function() { }, // empty reducer that doesn't do anything
"out": "collectionKeys" // output collection with results
})
var randomstringKeysList = db[mr.result].distinct("_id"),
orOperator = randomstringKeysList.map(function (key){
var o = {};
o["a."+ key +".setup"] = true;
return o;
}),
query = { "$or": orOperator };
db.collection.find(query);
I'm trying to delete all folders on MongoDB whose descriptions contain a number higher than 10. Can you tell me how to do that?
I've been trying desperately since hours...
Thanks very much!
Robomongo
You need a mechanism to get a list of the keys in the collection first, filter the list for the ones that have a number greater than 10 and then generate a query that you will use with the $unset operator in your update. Your update document should have this structure:
var update = {
"$unset": {
"p11": "",
"p12": "",
...
}
}
which you will use in your update as
db.collection.update({}, update, {multi: true});
You need the mapReduce() command to generate that update document. The following mapreduce operation will populate a separate collection with the document as the value:
db.collection.mapReduce(
function() {
var map = this;
for (var key in map) {
if (map.hasOwnProperty(key)){
num = parseInt(key.replace(/[^\d.]/g, '' ));
if (num > 10) emit(null, key);
}
}
},
function(key, values) {
return values.reduce(function(o, v) {
o[v] = "";
return o;
}, {});
},
{ "out": "filtered_keys" }
);
You can then run a query on the resultant collection to get the update document and do the actual update:
var update = {
"$unset": db.filtered_keys.findOne({"_id": null}).value
},
options = { "multi": true };
db.collection.update({}, update, options);
I have following model in mongoose. projects field is protected.
var UserProjectSchema = new Schema({
user : ObjectId
, projects : {type : [ObjectId], select:false} //protected field
, projectCount : Number
});
I want that protected field after update so that I could return the new set of projects.
UserProjectSchema.statics.addProject = function(userId, projectId) {
UserProject.findOneAndUpdate({
user:userId
},
{
$addToSet: {"projects" : projectId}
, $inc : {"projectCount" : 1}
},
{
upsert : true
//project : '+projects' it won't work
},
function(err, doc){
//doc.projects is undefined
// UserProject.findOne({user:userId},'+projects', function(err, doc){
// doc.projects is now available but this extra query ???
//})
});
}
var UserProject = mongoose.model('user_projects', UserProjectSchema);
Mongoose returns the updated document after successful query but lacks to specify the fields to project.
Is there any way to specify what fields to project after updating in mongoose so that I could remove the extra query ?
Include a select parameter in your options param and list all the fields you would like to project.
{
upsert : true,
select:{"projects":1} // all the fields you would want to select
}
I want update an _id field of one document. I know it's not really good practice. But for some technical reason, I need to update it.
If I try to update it I get:
db.clients.update({ _id: ObjectId("123")}, { $set: { _id: ObjectId("456")}})
Performing an update on the path '_id' would modify the immutable field '_id'
And the update is rejected. How I can update it?
You cannot update it. You'll have to save the document using a new _id, and then remove the old document.
// store the document in a variable
doc = db.clients.findOne({_id: ObjectId("4cc45467c55f4d2d2a000002")})
// set a new _id on the document
doc._id = ObjectId("4c8a331bda76c559ef000004")
// insert the document, using the new _id
db.clients.insert(doc)
// remove the document with the old _id
db.clients.remove({_id: ObjectId("4cc45467c55f4d2d2a000002")})
To do it for your whole collection you can also use a loop (based on Niels example):
db.status.find().forEach(function(doc){
doc._id=doc.UserId; db.status_new.insert(doc);
});
db.status_new.renameCollection("status", true);
In this case UserId was the new ID I wanted to use
In case, you want to rename _id in same collection (for instance, if you want to prefix some _ids):
db.someCollection.find().snapshot().forEach(function(doc) {
if (doc._id.indexOf("2019:") != 0) {
print("Processing: " + doc._id);
var oldDocId = doc._id;
doc._id = "2019:" + doc._id;
db.someCollection.insert(doc);
db.someCollection.remove({_id: oldDocId});
}
});
if (doc._id.indexOf("2019:") != 0) {... needed to prevent infinite loop, since forEach picks the inserted docs, even throught .snapshot() method used.
Here I have a solution that avoid multiple requests, for loops and old document removal.
You can easily create a new idea manually using something like:_id:ObjectId()
But knowing Mongo will automatically assign an _id if missing, you can use aggregate to create a $project containing all the fields of your document, but omit the field _id. You can then save it with $out
So if your document is:
{
"_id":ObjectId("5b5ed345cfbce6787588e480"),
"title": "foo",
"description": "bar"
}
Then your query will be:
db.getCollection('myCollection').aggregate([
{$match:
{_id: ObjectId("5b5ed345cfbce6787588e480")}
}
{$project:
{
title: '$title',
description: '$description'
}
},
{$out: 'myCollection'}
])
You can also create a new document from MongoDB compass or using command and set the specific _id value that you want.
As a very small improvement to the above answers i would suggest using
let doc1 = {... doc};
then
db.dyn_user_metricFormulaDefinitions.deleteOne({_id: doc._id});
This way we don't need to create extra variable to hold old _id.
Slightly modified example of #Florent Arlandis above where we insert _id from a different field in a document:
> db.coll.insertOne({ "_id": 1, "item": { "product": { "id": 11 } }, "source": "Good Store" })
{ "acknowledged" : true, "insertedId" : 1 }
> db.coll.aggregate( [ { $set: { _id : "$item.product.id" }}, { $out: "coll" } ]) // inserting _id you want for the current collection
> db.coll.find() // check that _id is changed
{ "_id" : 11, "item" : { "product" : { "id" : 11 } }, "source" : "Good Store" }
Do not use $match filter + $out as in #Florent Arlandis's answer since $out fully remove data in collection before inserting aggregate result, so effectively you will loose all data that don't match to $match filter