Hi I am trying to build an application which upserts data and fetches from the mongodb baser on the userid.This approach works fine for a single user.But when i try hitting for multiple users say 25 the data fetched seems to be null. Below is my upsert code
collection.update({'USER_ID': passVal.ID},
{'RESPONSE': Data}, { upsert: true }, function (err) {
if (err) {
console.log("Error in saving data");
}
var query = collection.findOne({'USER_ID': passVal.ID});
query.select('RESPONSE');
query.exec(function (err, data) {
if (err) return handleError(err);
console.log(data.RESPONSE);
});
})
I always get an error insome cases as data is null.I have written the read code in the call back of upsert only.I am stuck here any help regarding this will be much helpful.
Related
I am getting an unusual error message when trying to insert data into my mongodb database. I am attempting to perform a simple insertOne operation, not even referencing any key called $clusterTime
db.collection("listings").insertOne( objToInsert , function(err, res) {
if (err) { console.log(err); console.log("err"); return; }
console.log('success');
});
Solution provided by Mongodb at : https://jira.mongodb.org/browse/NODE-1627?page=com.atlassian.jira.plugin.system.issuetabpanels%3Aall-tabpanel
Basically, upgrade from v3.1.2 to v3.1.3
So, I only have a few documents in my Mongo DB. For example, I have this basic find request (see below) which takes 4 seconds to return a 1.12KB JSON, before the component re-render.
app.get('/mypath', (req, res) => {
MongoClient.connect(urlDb, (err, db) => {
let Mycoll = db.collection('Mycoll');
Mycoll.find({}).toArray( (err, data) => {
if (err) throw err;
else{
res.status(200).json(data);
}
})
db.close();
})
});
Sometimes for that same component to re-render, with the same request, it takes 8 seconds (which equals an eternity for an Internet user).
Is it supposed to take this long ? I can imagine a user of my app starting to think ("well, that doesn't work") and close it right before the results show.
Is there anything you could point me to to optimize the performance ? Any tool you would recommend to analyze what exactly causes this bottleneck ? Or anything I did wrong ?
At this stage, I don't incriminate React/Redux, because with no DB requests involved, my other components render fast.
I am writing a service class (mongo_service.js) in order to keep my CRUD operations seperate for a project.
Below is the code to update multiple items.
updateMultipleCollection(Model, searchObject, collectionNewToUpdate) {
return new Promise(function (resolve, reject) {
Model.update( searchObject, collectionNewToUpdate, {new:true, multi:true}, function (err, data) {
if (err) {
reject(err);
}
resolve (data);
console.info("Multiple updates successful");
});
});
};
This works fine but the promise won't return the updated objects and I was wondering whether there was any other way to overcome this??
NOTE: In mongoose documentation they have mentioned that .update() will not return the updated objects whereas .findOneAndUpdate() does.
you could do a .find() and that will return an array.
Then do a forEach over the array and do .save on each doc. The new doc should be in the callback of .save
router.get('/wiki/:topicname', function(req, res, next) {
var topicname = req.params.topicname;
console.log(topicname);
summary.wikitext(topicname, function(err, result) {
if (err) {
return res.send(err);
}
if (!result) {
return res.send('No article found');
}
$ = cheerio.load(result);
var db = req.db;
var collection = db.get('try1');
collection.insert({ "topicname" : topicname, "content": result }, function (err, doc){
if (err) {
// If it failed, return error
res.send("There was a problem adding the information to the database.");
}
else {
// And forward to success page
res.send("Added succesfully");
}
});
});
Using this code, I am trying to add the fetched content from Wikipedia in to the collection try1. The message "Added succesfully" is displayed. But the collection seems to be empty. The data is not inserted in the database
The data must be there, mongodb has { w: 1, j: true } write concern options by default so its only returns without an error if the document is truly inserted if there were any document to insert.
Things you should consider:
-Do NOT use insert function, its depricated use insertOne, insertMany or bulkWrite. ref.: http://mongodb.github.io/node-mongodb-native/2.1/api/Collection.html#insert
-The insert methods callback has two parameters. Error if there was an error, and result. The result object has several properties with could be used for after insert result testing like: result.insertedCount will return the number of inserted documents.
So according to these in your code you only test for error but you can insert zero documents without an error.
Also its not clear to me where do you get your database name from. Is the following correct in your code? Are you sure you are connected to the database you want to use?
var db = req.db;
Also you don't have to enclose your property names with " in your insert method. The insert should look something like this:
col.insertOne({topicname : topicname, content: result}, function(err, r) {
if (err){
console.log(err);
} else {
console.log(r.insertedCount);
}
});
Start your mongod server in a correct path,i.e, same path as that of what you are using to check the contents of collection.
sudo mongod --dbpath <actual-path>
I am trying to fetch all the records but with selected fields, I have tried the following ways but none works:
Post.find(
{
where: {},
select: ['title']
}
);
Post.find(
{},
{
fields: {
title: 1
}
}
);
As this answer points out, the fields param "WILL work as long as you pass other params with it such as limit or order."
Alternatively, if you want this throughout your application, you could define a custom toJSON function for your model, under attributes. If not, you could still define it under some other (e.g. filter) and use map to return the custom objects instead of the default model. Remember to take care of the control flow while using map though. Use async/promises/raw logic to avoid returning before all objects are processed.
The issue has been resolved in sails-mongo latest version:
https://github.com/balderdashy/waterline/issues/1098
Thanks
I've played with trying to get above answer to use limit or order to kick in the projection to no avail.
I did see this in the docs located here:
http://sailsjs.org/documentation/reference/waterline-orm/models/native
With an out of the box solution for exactly what you're doing (pasted here for ease of use).
Pet.native(function(err, collection) {
if (err) return res.serverError(err);
collection.find({}, {
name: true
}).toArray(function (err, results) {
if (err) return res.serverError(err);
return res.ok(results);
});
});
Swap out the response base things and change Pet to Post and, this ought to work in the sails console:
Post.native(function(err, collection) {
if (err) throw new Error(err);
collection.find({}, {
title: true
}).toArray(function (err, results) {
if (err) throw new Error(err);
console.log(results);
});
});
You'll still get the _id field, and if you don't want that then hit the Mongo docs on not getting those hint(title: true, _id: false)hint
Hope this helps!