I am trying to update the following document in Mongodb.
doc = { id : 10 , graph :[{userId:1,children:[2]},{userId:2,children:[]}]}
db.test.insert(doc)
then I perform two updates:
db.test.update( {'id':10,'graph.userId' : 1}, { $push:{'graph.$.children':10}})
db.test.update( {'id':10,'graph.userId' : 1},{ $push:{'graph':{'userId':10,'children':[]}}})
(Saddly :
db.test.update( {'id':10,'graph.userId' : 1},{ $push:{'graph.$.children':10},$push:{'graph':{'userId':10,'children':[]}}})
does not work)
Is there a way to update these simultaneously ?
Thanks a lot
You can bundle multiple update operations together, but the only issue with what you've written in pseudo code is that the elements you're pushing belong to different arrays (graph and graph.children respectively.) This needs to be done in two pushes.
Try this:
db.test.update( { id:10, 'graph.userId':1 },
{ $push:{'graph.$.children' : 4 }, $push:{'graph' : {'userId':4,'children':[]}} } )
The multiple keys in the modifier array stop it from working. You have to do two updates to do this if I read your shema right cos you are trying to push a new child onto the current position and push a new record into the subdocument of the parent.
The thing that stops it is the children[] setting. Mongo just does not know where to set that.
I suppose you could try:
db.test.update( {'id':10,'graph.userId' : 1},{ $push:{'graph.$.children':10},$pushAll:{'graph':{{'userId':10,'children':[]}}}})
But it is a long shot
Related
I have a document in my Mongo collection which has a field with the following structure:
"_id" : "F7WNvjwnFZZ7HoKSF",
"process" : [
{
"process_id" : "wTGqVk5By32mpXadZ",
"stages" : [
{
"stage_id" : "D6Huk89DGFsd29ds7",
"completed" : "N"
},
{
"stage_id" : "Msd390vekn09nvL23",
"completed" : "N"
}
]
}
]
I need to update the value of completed where the stage_id is equal to 'D6Huk89DGFsd29ds7' - the update query will not know which object in the stages array this value of stage_id will be in.
How do I do this?
Since you have nested arrays in your object, this is bit tricky and I'm not sure if this problem can be solved with help of just one update query.
However, if you happen to know index of your matching object in first array, in your case process[0] you can write your update query like.
db.collection.update(
{"process.stages.stage_id":"D6Huk89DGFsd29ds7"},
{$set:{"process.0.stages.$.completed":"Y"}}
);
Query above will work perfect with your test case. Again, there is still possibility of having multiple objects at root level and there is no guarantee that matching object will always be at 0 index.
Solution I proposed above will fail if you have multiple children of process and if matching index of object is not zero.
However, you can achieve your goal with help of client side programming. That is find matching document, modify on client side and replace whole document with new content.
Since this approach is very in efficient, I'll suggest that you should consider altering your document structure to avoid nesting. Create another collection and move content of process array there.
In the end, I removed the outer process block, so that the process_id and stages were in the root of the document - made the process of updating easier using:
MyColl.update(
{
_id: 'F7WNvjwnFZZ7HoKSF',
"stages.stage_id": 'D6Huk89DGFsd29ds7'
},
{
$set: {"stages.$.completed": 'Y'}
}
);
We have a mongodb document with the following structure: One of the document's fields is a map, and each map entry has several fields of it's own.
We want a way to update the value of one field inside a specific map entry using mogodb update query.
To clarify things, if we have the document as bellow, we want to update "callBackUrl" for entry 1 in the map "urlSettings" to "yadayada.com".
Is that possible at all?
SystemSettings : {
urlSettings : {
1 : {
callBackUrl : "blabla.com",
(more fields...)
},
2 : {
...
},
...
},
...
}
check the below query :
db.collection.update(
{"SystemSettings.urlSettings.1.callBackUrl" : "blabla.com"},
{"$set":{"SystemSettings.urlSettings.1.callBackUrl" : "yadayada.com"}}
);
I have a document something like this :
myDoc : {
_id : a101
name : John,
batch : [{
_id : batch101,
value : physics
},{
_id : batch102,
value : chemistry
},{
_id : batch103,
value : maths
}]
}
I want to update the "value" to "computers" where the batch._id is either "batch101" or "batch102" (not batch103).
Please help! Thanks in advance.
-Manish :)
As noted in comments on the orignal question, the best solution here might be to work with the document on the client side. I will break this down into a few steps:
1) Query for the document. You mentioned you are working in node, so this will be represented in JSON. Lets call this variable x
2) Go through your document finding the elements you want to update, this might look like:
for(i = 0; i < x.batch.length; i++) {
if(x.batch[i]._id == 'batch101') {
//do something
}
}
(this code is not complete, obviously, but gives you an idea of what you want)
3) Now, using this changed document, update the old document in mongoDB.
This process should allow you to achieve your goal of updating certain elements in the batch list.
I need help incrementing value of all keys in participants without having to know name of the keys inside of it.
> db.conversations.findOne()
{
"_id" : ObjectId("4faf74b238ba278704000000"),
"participants" : {
"4f81eab338ba27c011000001" : NumberLong(2),
"4f78497938ba27bf11000002" : NumberLong(2)
}
}
I've tried with something like
$mongodb->conversations->update(array('_id' => new \MongoId($objectId)), array('$inc' => array('participants' => 1)));
to no avail...
You need to redesign your schema. It is never a good idea to have "random key names". Even though MongoDB is schemaless, it still means you need to have defined key names. You should change your schema to:
{
"_id" : ObjectId("4faf74b238ba278704000000"),
"participants" : [
{ _id: "4f81eab338ba27c011000001", count: NumberLong(2) },
{ _id: "4f78497938ba27bf11000002", count: NumberLong(2) }
]
}
Sadly, even with that, you can't update all embedded counts in one command. There is currently an open feature request for that: https://jira.mongodb.org/browse/SERVER-1243
In order to still update everything, you should:
query the document
update all the counts on the client side
store the document again
In order to prevent race conditions with that, have a look at "Compare and Swap" and following paragraphs.
It is not possible to update all nested elements in one single move in current version of MongoDB. So I can advice to use "foreach {}".
Read realted topic: How to Update Multiple Array Elements in mongodb
I hope this feature will be implemented in next version.
I have the following collection:
{
"Milestones" : [
{ "ActualDate" : null,
"Index": 0,
"Name" : "milestone1",
"TargetDate" : ISODate("2011-12-13T22:00:00Z"),
"_id" : ObjectId("4ee89ae7e60fc615c42e28d1")},
{ "ActualDate" : null,
"Index" : 0,
"Name" : "milestone2",
"TargetDate" : ISODate("2011-12-13T22:00:00Z"),
"_id" : ObjectId("4ee89ae7e60fc615c42e28d2") } ]
,
"Name" : "a", "_id" : ObjectId("4ee89ae7e60fc615c42e28ce")
}
I want to update definite documents: that have specified _id, List of Milestones._id and ActualDate is null.
I dotnet my code looks like:
var query = Query.And(new[] { Query.EQ("_id", ObjectId.Parse(projectId)),
Query.In("Milestones._id", new BsonArray(values.Select(ObjectId.Parse))),
Query.EQ("Milestones.ActualDate", BsonNull.Value) });
var update = Update.Set("Milestones.$.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