I’m using upsert with the updateOne() method as bellow to perform an update.
db.practice.updateOne(
{“title”:“Night Life”},
{$set: detail},
{upsert: true}
)
My query returns the following:
{
"acknowledged" : true,
"matchedCount" : 0,
"modifiedCount" : 0,
"upsertedId" : ObjectId("5f8884fed29ded706c3c6737")
}
Below is the detail variable:
let detail = {
“title” : “Night Life”,
“year” : 2021,
“rated” : “PG-13”,
“released” : 2021,
“runtime” : 60,
“countries” : [
“USA”,
“UK”
],
“genres” : [
“comedy”,
“drama”
],
“director” : “Alpha Ly”,
“actors” : [
“Alpha Ly”,
“Kris Dasha”,
“Hope Grace”
]
}
When I check my collection in Compass, I don’t see the document with the ObjectId("5f8884fed29ded706c3c6737
However, when I run the following command db.practice.find({"director": "Alpha Ly"}).pretty(),
it returns the entry I've looking for in Compass.
NB: the number of documents in my collection is still the same as created.
What seems to be the problem here. Why Compass is not displaying the entry?
It seems like I was not using the correct database.
In order to execute the command, I was supposed to use the use command followed by the name of my database to switch to my database. Since I didn't, the update query created another collection and inserted the document there. Therefore, I couldn't find it in my database.
Thanks
Related
What's the difference between insert(), insertOne(), and insertMany() methods on MongoDB. In what situation should I use each one?
I read the docs, but it's not clear when use each one.
What's the difference between insert(), insertOne() and insertMany() methods on MongoDB
db.collection.insert() as mentioned in the documentation inserts a document or documents into a collection and returns
a WriteResult object for single inserts and a BulkWriteResult object for bulk inserts.
> var d = db.collection.insert({"b": 3})
> d
WriteResult({ "nInserted" : 1 })
> var d2 = db.collection.insert([{"b": 3}, {'c': 4}])
> d2
BulkWriteResult({
"writeErrors" : [ ],
"writeConcernErrors" : [ ],
"nInserted" : 2,
"nUpserted" : 0,
"nMatched" : 0,
"nModified" : 0,
"nRemoved" : 0,
"upserted" : [ ]
})
db.collection.insertOne() as mentioned in the documentation inserts a document into a collection and returns a document which look like this:
> var document = db.collection.insertOne({"a": 3})
> document
{
"acknowledged" : true,
"insertedId" : ObjectId("571a218011a82a1d94c02333")
}
db.collection.insertMany() inserts multiple documents into a collection and returns a document that looks like this:
> var res = db.collection.insertMany([{"b": 3}, {'c': 4}])
> res
{
"acknowledged" : true,
"insertedIds" : [
ObjectId("571a22a911a82a1d94c02337"),
ObjectId("571a22a911a82a1d94c02338")
]
}
In what situation should I use each one?
The insert() method is deprecated in major driver so you should use the
the .insertOne() method whenever you want to insert a single document into your collection and the .insertMany when you want to insert multiple documents into your collection. Of course this is not mentioned in the documentation but the fact is that nobody really writes an application in the shell. The same thing applies to updateOne, updateMany, deleteOne, deleteMany, findOneAndDelete, findOneAndUpdate and findOneAndReplace. See Write Operations Overview.
db.collection.insert():
It allows you to insert One or more documents in the collection. Syntax:
Single insert: db.collection.insert({<document>});
Multiple insert:
db.collection.insert([
, , ...
]);
Returns a WriteResult object: WriteResult({ "nInserted" : 1 });
db.collection.insertOne():
It allows you to insert exactly 1 document in the collection. Its syntax is the same as that of single insert in insert().
Returns the following document:
{
"acknowledged" : true,
"insertedId" : ObjectId("56fc40f9d735c28df206d078")
}
db.collection.insertMany():
It allows you to insert an array of documents in the collection. Syntax:
db.collection.insertMany(
{ [ <document 1> , <document 2>, ... ] });
Returns the following document:
{
"acknowledged" : true,
"insertedIds" : [
ObjectId("562a94d381cb9f1cd6eb0e1a"),
ObjectId("562a94d381cb9f1cd6eb0e1b"),
ObjectId("562a94d381cb9f1cd6eb0e1c")
]
}
All three of these also allow you to define a custom writeConcern and also create a collection if it doesn't exist.
There is also a difference in error handling, check here. The insert command returns a document in both success and error cases. But the insertOne and insertMany commands throws exceptions. Exceptions are easier to handle in code, than evaluating the returned document to figure out errors. Probably the reason why they are deprecated in the drivers as mentioned in sstyvane's answer.
Also to add to another answer, if the user calls the InsertOne function instead of InsertMany and passes the array of documents to insert. then it is also allowed and will not give any errors. It will create only one document which will have an array of these documents. so be careful.
If the collection does not exist, then the insertOne() method creates the collection. If you input the same data again, mongod will create another unique id to avoid duplication.
While running a query i want a result of that query into another file
My query is running successfully in mongo terminal.
db.questions.find({"question" : {$regex : ".*.*"}},{question :1,_id:0,id:1});
{ "id" : 0, "question" : "Amount was debited from my account, but ticket was not
generated. What should I do now?" }
{ "id" : 1, "question" : "How safe is goCash?" }
{ "id" : 2, "question" : "How referral program and goCash works?" }
Now check following image:
here
By this i can write in any type of file by just adding >> filename.extension
Now the main problem is with this one:
When i use find instead of findOne and use a regular expression, it shows unexpected token
Anyone knows how i can modify it to get the desired result.
You are using "(qoutes) inside the command line. Try using {'question' : { \$regex : '.*'}}.
Further the db.collection.find() method returns a cursor. Redirecting it to a file will just write the cursor json.To access the documents, you need to iterate the cursor.
mongo localhost/database -eval "var cursor = {'question' : { \$regex : '.*'}}; while(cursor.hasNext()){ printjson( cursor.next())}"
All the examples in the blog return result as json format.
You can also use any of the mongo-drivers to write your result to a file.
I'm trying to find records in MongoDB that are created outside a specific period. The query to search for records inside a specific period is pretty straightforward:
db.test.find({"Published":{'$gt':"2011-08-02", '$lt':"2011-08-06"}})
So naturally, I tried this for "outside" a specific range:
db.test.find({'$not':{"Published":{'$gt':"2011-08-02", '$lt':"2011-08-06"}}})
But this returns an empty result, while there are definately records published then.
What query should I use instead? Can anyone help me? I'm using raw mongo queries.
Thanks in advance
--- UPDATE ---
I found that the following query works, but it doesn't look like the perfect solution:
db.test.find(
{'$or': [
{"Published":{'$lt':"2011-02-02"}},
{"Published":{'$gt':"2011-08-06"}}
]}
)
Is there a cleaner way to do it?
You are putting the $not in the wrong place. Try this:
db.test.find({"Published":{ $not:{$gt:"2011-08-02", $lt:"2011-08-06"} } })
For details, see the MongoDB docs about the $notoperator.
Edit as because of the comment this solution would not work:
> db.dates.find()
{ "_id" : ObjectId("5492d46ef6226b581c80c0a2"), "a" : 1, "date" : "2011-08-04" }
{ "_id" : ObjectId("5492d4e2f6226b581c80c0a3"), "a" : 2, "date" : "2011-08-07" }
> db.dates.find({date:{$not:{$gt:"2011-08-02",$lt:"2011-08-06"}}})
{ "_id" : ObjectId("5492d4e2f6226b581c80c0a3"), "a" : 2, "date" : "2011-08-07" }
I have a database of person documents. Each has a field named photos, which is an array of photo documents. I would like to add a new 'reviewed' flag to each of the photo documents and initialize it to false.
This is the query I am trying to use:
db.person.update({ "_id" : { $exists : true } }, {$set : {photos.reviewed : false} }, false, true)
However I get the following error:
SyntaxError: missing : after property id (shell):1
Is this possible, and if so, what am I doing wrong in my update?
Here is a full example of the 'person' document:
{
"_class" : "com.foo.Person",
"_id" : "2894",
"name" : "Pixel Spacebag",
"photos" : [
{
"_id" : null,
"thumbUrl" : "http://site.com/a_s.jpg",
"fullUrl" : "http://site.com/a.jpg"
},
{
"_id" : null,
"thumbUrl" : "http://site.com/b_s.jpg",
"fullUrl" : "http://site.com/b.jpg"
}]
}
Bonus karma for anyone who can tell me a cleaner why to update "all documents" without using the query { "_id" : { $exists : true } }
For those who are still looking for the answer it is possible with MongoDB 3.6 with the all positional operator $[] see the docs:
db.getCollection('person').update(
{},
{ $set: { "photos.$[].reviewed" : false } },
{ multi: true}
)
Is this possible, and if so, what am I doing wrong in my update?
No. In general MongoDB is only good at doing updates on top-level objects.
The exception here is the $ positional operator. From the docs: Use this to find an array member and then manipulate it.
However, in your case you want to modify all members in an array. So that is not what you need.
Bonus karma for anyone who can tell me a cleaner why to update "all documents"
Try db.coll.update(query, update, false, true), this will issue a "multi" update. That last true is what makes it a multi.
Is this possible,
You have two options here:
Write a for loop to perform the update. It will basically be a nested for loop, one to loop through the data, the other to loop through the sub-array. If you have a lot of data, you will want to write this is your driver of choice (and possibly multi-thread it).
Write your code to handle reviewed as nullable. Write the data such that if it comes across a photo with reviewed undefined then it must be false. Then you can set the field appropriately and commit it back to the DB.
Method #2 is something you should get used to. As your data grows and you add fields, it becomes difficult to "back-port" all of the old data. This is similar to the problem of issuing a schema change in SQL when you have 1B items in the DB.
Instead just make your code resistant against the null and learn to treat it as a default.
Again though, this is still not the solution you seek.
You can do this
(null, {$set : {"photos.reviewed" : false} }, false, true)
The first parameter is null : no specification = any item in the collection.
"photos.reviewed" should be declared as string to update subfield.
You can do like this:
db.person.update({}, $set:{name.surname:null}, false, true);
Old topic now, but this just worked fine with Mongo 3.0.6:
db.users.update({ _id: ObjectId("55e8969119cee85d216211fb") },
{ $set: {"settings.pieces": "merida"} })
In my case user entity looks like
{ _id: 32, name: "foo", ..., settings: { ..., pieces: "merida", ...} }
I have the following collection:
{
"Milestones" : [
{ "ActualDate" : null,
"Index": 0,
"Name" : "milestone1",
"TargetDate" : ISODate("2011-12-13T22:00:00Z"),
"_id" : ObjectId("4ee89ae7e60fc615c42e28d1")},
{ "ActualDate" : null,
"Index" : 0,
"Name" : "milestone2",
"TargetDate" : ISODate("2011-12-13T22:00:00Z"),
"_id" : ObjectId("4ee89ae7e60fc615c42e28d2") } ]
,
"Name" : "a", "_id" : ObjectId("4ee89ae7e60fc615c42e28ce")
}
I want to update definite documents: that have specified _id, List of Milestones._id and ActualDate is null.
I dotnet my code looks like:
var query = Query.And(new[] { Query.EQ("_id", ObjectId.Parse(projectId)),
Query.In("Milestones._id", new BsonArray(values.Select(ObjectId.Parse))),
Query.EQ("Milestones.ActualDate", BsonNull.Value) });
var update = Update.Set("Milestones.$.ActualDate", DateTime.Now.Date);
Coll.Update(query, update, UpdateFlags.Multi, SafeMode.True);
Or in native code:
db.Projects.update({ "_id" : ObjectId("4ee89ae7e60fc615c42e28ce"), "Milestones._id" : { "$in" : [ObjectId("4ee89ae7e60fc615c42e28d1"), ObjectId("4ee89ae7e60fc615c42e28d2"), ObjectId("4ee8a648e60fc615c41d481e")] }, "Milestones.ActualDate" : null },{ "$set" : { "Milestones.$.ActualDate" : ISODate("2011-12-13T22:00:00Z") } }, false, true)
But only the first item is being updated.
This is not possible in current moment. Flag multi in update means update of multiple root documents. Positional operator can match only one nested array item. There is such feature in mongodb jira. You can vote up and wait.
Current solution can be only load document, update as you wish and save back or multiple atomic update for each nested array id.
From documentation at mongodb.org:
Currently the $ operator only applies to the first matched item in the
query
As answered by Andrew Orsich, this is not possible for the moment, at least not as you wish. But loading the document, modifying the array then saving it back will work. The risk is that some other process could modify the array in the meantime, so you would overwrite its changes. To avoid this, you can use optimistic locking, especially if the array is not modified every second.
load the document, including a new attribute: milestones_version
modify the array as needed
save back to mongodb, but now add a query constraint on the milestones_version, and increment it:
db.Projects.findAndModify({
query: {
_id: your_project_id,
milestones_version: expected_milestones_version
},
update: {
$set: {
Milestones: modified_milestones
},
$inc: {
milestones_version: 1
}
},
new: 1
})
If another process modified the milestones array (and hence the milestones_version) before we did, then this command will do nothing and simply return null. We just need to reload the document and try again. If the array is not modified every second, then this will be very rare and will not have any impact on performance.
The main problem with this solution is that you have to edit every Project, one by one (no multi: true). You could still write a javascript function and have it run on the server though.
According to their JIRA page "This new feature is available starting with the MongoDB 3.5.12 development version, and included in the MongoDB 3.6 production version"
https://jira.mongodb.org/browse/SERVER-1243