The mongodb $or operator works as intended outside of a meteorjs context:
db.users.find({$or: [{email: 'some#mail.com'},{city: 'atlanta'}]});
I get results for any document that has email some#mail.com or city of atlanta.
The same query in Meteor syntax doesn't yield the same results :
Users = new Meteor.Collection("users");
Users.find({$or: [{email: 'some#mail.com'},{city: 'atlanta'}]});
I've read the meteor docs - http://docs.meteor.com/#find - and since it doesn't say anything about it, I'm assuming it should run just the same as a mongodb 1.6+ instance?
find returns a cursor object. You need to use a fetch to get the array of values. Try:
console.log(Users.find({$or: [{email: 'some#mail.com'},{city: 'atlanta'}]}).fetch());
Related
I am using official mongo driver for Golang: go.mongodb.org/mongo-driver/mongo
Preface
In this driver, I could not found any method for returning one single object from aggregation query.
driver aggregation documentation
Problem
The problem I am facing with this is if I have some documents which should be filtered and only first one should be returned, then I forcefully need to get all documents and return document on 0 index. In my knowledge, this is not optimized.
I have only one method for aggregation here, which returns cursor of multiple objects:
Is it possible to get single object in aggregation in this driver ?
Aggregation always returns a list of documents, but you may use the $limit stage to only return one document.
bson.M{"$limit": 1}
I am trying to write a simple query in MongoDb using PyMongo driver as such
mongo.db.people.find_one({'name': 'Tést Name'})
mongo.db.people.find_one({'name': 'Test_O%27Name'})
Both of these queries are returning null. I have checked to make sure the data exists in the db. How do I change the query so that find() is able to find it?
Thanks
You can use like this
db.myCollection.find({ myKey : /.*\$tes.*/i });
You have to escape $ by :
Unable to pull all the documents from MongoDB collection using Jmeter JSR233 sampler.
I’m trying to pull all the documents from MongoDB collection to jmeter to pass it as a test case for my performance test execution.
The below works -
myDoc = collection.find(eq("ABCValue", "ABC")).first();
log.info myDoc.toJson();
collection.find(...query...).last(); also works.
I’m able to pull the first and last value from MongoDB collection for that query. However unable to pull all the documents from the collection when I try to use the following -
myDoc = collection.find();
log.info myDoc.toJson();
This does not work only in Jmeter. Please help!
To print all documents returned from find(), you need to iterate over the documents returned
for (Document cur : collection.find()) {
log.info cur.toJson();
}
The find() method returns a FindIterable() instance that provides a fluent interface for chaining other methods.
MongoDb query
I am new to MongoDB, I just started learning recently.When I am using a query command for instance, db.tests.find({"by":"Srihari"}) .It is not giving any output. Is there any wrong with my query? Please help!
From the screenshot you've shared following document exists in your tests collection:
{"username": "srihari"}
{"username": "srih"}
{"username": "srh"}
{"username": "sh"}
The query you're sending to mongodb is :
db.tests.find({"by":"Srihari"})
There isn't any document in tests collection that matches your query.
However, you can query like this:
db.tests.find({"username": "sh"})
will definately return the result.
In MongoDB you specify equality conditions, using <field>:<value> expressions in the query filter. So db.tests.find({"by":"Srihari"}) is looking for all documents where the field "by" has the value "Srihari".
Since your document has the format
{
username: "srihari"
}
your query should be:
db.tests.find({username: "srihari"})
You can see more examples here: https://docs.mongodb.com/manual/tutorial/query-documents/
This is such a weird problem. I think it has to do with how I am querying the document. It seems like the Meteor API has changed to query documents but the docs on the website are the same.
Here is a document in the database:
meteor:PRIMARY> db.studies.findOne()
{ "_id" : ObjectId("56c12e6537014a66b16771e7"), "name" : "Study 1" }
I have subscribed to get all documents and here is what I am trying in the console to get the documents.
var study = Studies.findOne() // This works.
It returns:
_id: MongoID.ObjectID
_str: "56c12e6537014a66b16771e7"
name: 'Study 1'
I just started a new Meteor project with React. I see that my collection is returning _id: MongoId.ObjectId
This is different, I have been using Meteor for awhile with Blaze and I can't remember it returning MongoID.ObjectID instead of just the string
But now if I try and find just that one document, it does not work.
var study = Studies.findOne("56c12e6537014a66b16771e7");
or
var study = Studies.findOne({_id: "56c12e6537014a66b16771e7"});
I am positive I am queuing for the right _id field. I have double checked the ID. Why does trying to find this one document not work?
Please let me know how I can query for a document. Has something changed with Meteor? The documentation still says you can search by id string.
You need to explicitly cast object id string to an ObjectID
var study = Studies.findOne({_id: new Meteor.Collection.ObjectID("56c12e6537014a66b16771e7")});
#Jaco has the correct answer, but I wanted to answer here to clarify what the higher level issue was.
The reason why my find query was not following syntax in Meteor docs is because I inserted the document into MongoDB directly, instead of through the Meteor API.
If you insert the document directly into MongoDB, you have to query the document using the syntax #Jaco mentioned in his answer.
Similar question: Meteor - Find a document from collection via Mongo ObjectId
So instead of changing my query code, I just deleted the document I inserted directly into MongoDB, and inserted a documented using the console in the browser.
Now I can query the document like normal.
So the root of the issue is that if you insert the document directly into MongoDB, you don't get the same type of document as you would if you insert the document using the Meteor API.