Update specific field in an array of object in a MongoDb Document - node.js

I have a document with that format :
{
"field1":"string",
"field2":123,
"field3":
[
{
"subField1":"string",
"subField2": object,
// other fields after
},
{
"subField1":"string",
"subField2": object,
// other fields after
},
// other fields after
]
// other fields after
}
I want to update at once the field3.$.subField2 field only, with a different value in each of the elements of the array composing field3.
Does anyone knows how to properly do it ?
One reason I want to do this is I have several asynchronous operations that are meant to update differents fields of the array field, and I have concurrency issues...
I tried with findOneAndUpdate(query, $set{"field3.$.subField2": arrayOfValues}) but it does not works, it seems I can only pass one single value that would be set to each element of the array (all the same).
arrayOfValues would be of course an array with only the values I want with the matching indexes and same size of the document's array.

Related

How to obtain nested fields within JSON

Background:
I wish to update a nested field within my JSON document. I want to query for all of the "state" that equal "new"
{
"id": "123"
"feedback" : {
"Features" : [
{
"state":"new"
}
]
}
This is what I have tried to do:
Since this is a nested document. My query looks like this:
SELECT * FROM c WHERE c.feedback.Features.state = "new"
However, I keep ending up with zero results when I know that this exists within the database. What am I doing wrong? Maybe I am getting 0 results because the Features is an array?
Any help is appreciated
For arrays, you'll need to use ARRAY_CONTAINS(). For example, in your case:
SELECT *
FROM c
WHERE ARRAY_CONTAINS(c.feedback.Features,{'state': 'new'}, true)
The 3rd parameter specifies that you're searching within documents within the array, not scalar values.

Updating firestore document nested data overwrites it

I'm trying to set some new fields in a nested dict within a Firestore document, which results in the data being overwritten.
Here's where I write the first part of the info I need:
upd = {
"idOffer": {
<offerId> : {
"ref" : <ref>,
"value" : <value>
}
}
}
<documentRef>.update(upd)
So output here is something like:
<documentid>:{idOffer:{<offerId>:{ref:<ref>, value:<value>}}}
Then I use this code to add some fields to the current <offerId> nested data:
approval = {
"isApproved" : <bool>,
"dateApproved" : <date>,
"fullApproval" : <bool>
}
<documentRef>.update({
"idOffer.<offerId>" : approval
})
From which I expect to get:
<documentid>:{idOffer:{<offerId>:{ref:<ref>, value:<value>, isApproved:<bool>,dateApproved:<date>,fullApproval:<bool>}}}
But I end up with:
<documentid>:{idOffer:{<offerId>:{isApproved:<bool>,dateApproved:<date>,fullApproval:<bool>}}}
Note: I use <> to refer to dynamic data, like document Ids or References.
When you call update with a dictionary (or map, or object, or whatever key/value pair structure used in other languages), the entire set of data behind the given top-level keys are going to be replaced. So, if you call update with a key of idOffer.<offerId>, then everything under that key is going to be replaced, while every other child key of the idOffer level will remain unchanged.
If you don't want to replace the entire object behind the key, then be more specific about which children you'd like to update. In your example, instead of updating a single idOffer.<offerId> key, specify three keys for the nested children:
idOffer.<offerId>.isApproved
idOffer.<offerId>.dateApproved
idOffer.<offerId>.fullApproval
That is to say, the dictionary you pass should have three keyed entries like this at the top level, rather than a single key of idOffer.<offerId>.

Increment nested field value in mongodb if exists or create nested fields

I need to increment the multi level nested field value if it exists or create the complete nested field Object structure.
Structure of my document
Doc1 {
_id:ObjectId(),
myField: {
nested:{
x: 5,
y: 10,
z: 20
}
}
}
Goal Explanation: I need a way to write a single query:
If myField exists: Increment the value of my nested field
myField.nested.x by 10.
If myField does not exists: Create the below field with initial values same as given in the Doc1.
Attempt and explanation:
db.collection('collectionName').findOneAndUpdate(
{_id:"userId","myField" : { $exists : true }},
{$inc:{'myField.nested.x':10}
})
This way, I can increment the nested field if it exists but in case of non existence I cannot set myField as same as Doc1.
Although, I can use another query after response in my NodeJs callback to achieve my required behaviour. But I need some elegant solution in a single query.
I am using MongoDB version 4.0.4, Thanks in Advance.
Try this query
If the field does not exist, $inc creates the field and sets the field to the specified value.
db.collection('collectionName').findOneAndUpdate({_id:"userId"},
{$inc:{'myField.nested.x':10}
})

How do you query a CouchDB view that emits complex keys?

Given a CouchDB view that emits keys of the following format:
[ "part1", { "property": "part2" } ]
How can you find all documents with a given value for part1?
If part2 was a simple string rather than an object startkey=["part1"]&endkey=["part1",{}] would work. The CouchDB docs state the following:
The query startkey=["foo"]&endkey=["foo",{}] will match most array keys with "foo" in the first element, such as ["foo","bar"] and ["foo",["bar","baz"]]. However it will not match ["foo",{"an":"object"}]
Unfortunately, the documentation doesn't offer any suggestion on how to deal with such keys.
The second element of your endkey value needs to be an object that collates after any possible value of the second element of your key. Objects are compared by property-by-property (for example, {"a":1} < {"a":2} < {"b":1}) so the best way to do this is to set the first property name in your endkey to a very large value:
startkey=["part1"]&endkey=["part1", { "\uFFF0": false }]
The property name of \uFFF0 should collate after any other property names in the second key element, and even works when the second element is an empty object or has more than one property.

Mongo DB C# code using 2 level , 3 level and 4 level of array

I have to update in C# code using MongoDB. Here I had implement 2nd level array of update in below (subBranchindex is taken in a generic list object):-
for (var index = 0; index < subBranchindex.Count; index++)
{
if (subBranchindex[index]._id == new ObjectId(subBranchid))
{
IMongoQuery queryEdit = Query.EQ("BranchOffice.SubBranchlist._id", new ObjectId(subBranchid));
UpdateBuilder update = Update.Set("BranchOffice.$.SubBranchlist."+ index +".Name",subBranch.SubName).
SafeModeResult s = dc.Collection.Update(queryEdit, update,
UpdateFlags.None, SafeMode.True);
}
}
Here 2nd level array, I was using (for loop Statement) to taken Index value for array. Next I can use 3rd, 4th and 5th level of array means more than (for loop statement) will be assign. So don't need [for loop Statement] and also don't need to assign hardcore number in index.
For example: ("BranchOffice.$.SubBranchlist.0.Name",subBranch.SubName). Here Don't Hardcore number[index] 0 or 1 or 2. "2nd" level array more than 100 record is there.
Is there any way I can use to array index value? Please explain how to solve this probelm. Please explain me with Example.
Based on your example above, my understanding of your schema is the following:
The top-level document has a BranchOffice field
BranchOffice is an array of objects
Each object within BranchOffice has an _id, SubName and SubBranchlist field
SubBranchlist is an array of objects
Each object within SubBranchlist has a Name field
Your update statement appears to be copying the SubName field to each Name field among objects within SubBranchlist (a sibling field of SubName).
Using the property path syntax to select fields through arrays (e.g. SubBranchlist.0.Name), there is no "wildcard" index that will allow you to modify Name fields among all objects in the array.
On a somewhat related note, the $ positional operator only applies to the first-matched array element, so you cannot use that to update multiple array elements. In your case, it would not be an option anyway, since you're using the positional operator for the BranchOffice array field.
You can either issue a series of update queries (for each element in SubBranchlist), or consider using $set to modify the entire SubBranchlist array in one query. The downside with using $set is that you'll need to read and write back the entire array, which may be a problem if other, concurrent operations are also issuing updates to the array.

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