i have a trouble.
i need to update value in nected array (array in array).
For example i have document like this:
{
"_id" : ObjectId("59eccf5ea7f6ff30be74d8ce"),
"name" : "some name",
"description" : "some description",
"users" : [
{
"id" : ObjectId("59d1549f4f5c6f6e0f1d6576"),
"technologies" : [
{"id": ObjectId("59450bc718fda360fdf4a719")},
]
},
{
"id": ObjectId("59d1549e4f5c6f6e0f1d6571"),
"technologies": [
{"id": ObjectId("59450f8318fda360fdf4a78b")},
{"id": ObjectId("59450bc718fda360fdf4a719")},
{"id": ObjectId("59450e3f18fda360fdf4a767")}
]
},
{
"id": ObjectId("59d154a44f5c6f6e0f1d65af"),
"technologies": [
ObjectId("59450f8318fda360fdf4a78b")
]
}
]
}
i need to delete exact technology from exact user. i know only:
_id - global document id
userId: 'users.id' element
technologyId: 'users.$.technologies.$.id' id of technology item that should be deleted
documentation of mongo says that i cant use two $ in update statement, but maybe is exists some actions to awoid this?
Try the following:
db.yourColl.update(
{
"_id": ObjectId("59eccf5ea7f6ff30be74d8ce"),
"users.id": ObjectId("59d1549e4f5c6f6e0f1d6571")
},
{
"$pull": {
"users.$.technologies": {
"id": ObjectId("59450bc718fda360fdf4a719")
}
}
}
)
The result should be:
{
"_id" : ObjectId("59eccf5ea7f6ff30be74d8ce"),
"name" : "some name",
"description" : "some description",
"users" : [
{
"id" : ObjectId("59d1549f4f5c6f6e0f1d6576"),
"technologies" : [
{
"id" : ObjectId("59450bc718fda360fdf4a719")
}
]
},
{
"id" : ObjectId("59d1549e4f5c6f6e0f1d6571"),
"technologies" : [
{
"id" : ObjectId("59450f8318fda360fdf4a78b")
},
{
"id" : ObjectId("59450e3f18fda360fdf4a767")
}
]
},
{
"id" : ObjectId("59d154a44f5c6f6e0f1d65af"),
"technologies" : [
ObjectId("59450f8318fda360fdf4a78b")
]
}
]
}
Related
Using Mongo 4.4
I'm looking to to lookups across collections and add a human readable value from the target collection to the source collection using a aggregate.
This works fine for individual values, but for some lookups the ObjectIds are in objects in arrays, and I can't get that work. I can pull all the values back, but not place the individual values in the array objects.
In this test case, I have a library database with a books collection and a subscribers collection. The subscribers have a checkouts entry with is an array of objects, containing a reference to a book, and the checkout date. I want to add the book title to each object in the array.
Test Database:
books collection:
[
{
"_id" : ObjectId("63208c9f0d97eff0cfbefde6"),
"title" : "There and back again",
"author" : "Bilbo Baggins",
"publisher" : "Middle Earth Books"
},
{
"_id" : ObjectId("63208cd10d97eff0cfbeff02"),
"title" : "Two Towers",
"author" : "JRR Tolkin",
"publisher" : "Dude Books"
},
{
"_id" : ObjectId("63208cf10d97eff0cfbeffa3"),
"title" : "Dune",
"author" : "Frank Herbert",
"publisher" : "Classic Books"
},
{
"_id" : ObjectId("63208d1d0d97eff0cfbf0087"),
"title" : "Old Man's War",
"author" : "John Scalzi",
"publisher" : "Old Man Books"
}
]
subscribers collection:
[
{
"_id" : ObjectId("63208c2e0d97eff0cfbefb46"),
"name" : "Tom",
"checkouts" : [
{
"bookId" : ObjectId("63208cd10d97eff0cfbeff02"),
"checkoutDate" : ISODate("2022-01-01T21:21:20.202Z")
},
{
"bookId" : ObjectId("63208d1d0d97eff0cfbf0087"),
"checkoutDate" : ISODate("2022-01-02T21:22:20.202Z")
}
],
"address" : "123 Somewhere"
},
{
"_id" : ObjectId("63208c4e0d97eff0cfbefc1f"),
"name" : "Bob",
"checkouts" : [],
"address" : "123 Somewhere"
},
{
"_id" : ObjectId("63208c640d97eff0cfbefc9a"),
"name" : "Mary",
"checkouts" : [],
"address" : "123 Somewhere Else"
}
Desired Output for user Tom:
{
"_id" : ObjectId("63208c2e0d97eff0cfbefb46"),
"name" : "Tom",
"checkouts" : [
{
"bookId" : ObjectId("63208cd10d97eff0cfbeff02"),
"checkoutDate" : ISODate("2022-01-01T21:21:20.202Z"),
"title" : "Two Towers"
},
{
"bookId" : ObjectId("63208d1d0d97eff0cfbf0087"),
"checkoutDate" : ISODate("2022-01-02T21:22:20.202Z"),
"title" : "Old Man's War"
}
],
"address" : "123 Somewhere",
}
Using this aggregate:
db.getCollection('subscribers').aggregate([
{$match: {_id: ObjectId("63208c2e0d97eff0cfbefb46") } },
{$lookup: {from: "books", localField: "checkouts.bookId", foreignField: "_id", as: "book_tmp_field" }},
{$addFields: { "checkouts.title": "$book_tmp_field.title"}},
{$project: { book_tmp_field: 0}}
])
This is the closest I can get:
{
"_id" : ObjectId("63208c2e0d97eff0cfbefb46"),
"name" : "Tom",
"checkouts" : [
{
"bookId" : ObjectId("63208cd10d97eff0cfbeff02"),
"checkoutDate" : ISODate("2022-01-01T21:21:20.202Z"),
"title" : [
"Two Towers",
"Old Man's War"
]
},
{
"bookId" : ObjectId("63208d1d0d97eff0cfbf0087"),
"checkoutDate" : ISODate("2022-01-02T21:22:20.202Z"),
"title" : [
"Two Towers",
"Old Man's War"
]
}
],
"address" : "123 Somewhere"
}
Before performing the lookup, you should UNWIND the checkouts array. After all the processing is done, group the documents, to obtain the checkouts in the array. Finally, project your desired output document. Like this:
db.subscribers.aggregate([
{
$match: {
_id: ObjectId("63208c2e0d97eff0cfbefb46")
}
},
{
"$unwind": "$checkouts"
},
{
$lookup: {
from: "books",
localField: "checkouts.bookId",
foreignField: "_id",
as: "book_tmp_field"
}
},
{
$addFields: {
"checkouts.title": "$book_tmp_field.title"
}
},
{
$project: {
book_tmp_field: 0
}
},
{
"$group": {
"_id": {
_id: "$_id",
address: "$address",
name: "$name"
},
"checkouts": {
"$push": "$checkouts"
}
}
},
{
"$replaceRoot": {
"newRoot": {
"$mergeObjects": [
"$_id",
{
checkouts: "$checkouts"
}
]
}
}
}
])
Here's the playground link.
I am trying to update data of "array1.array2._id": ObjectId("627a6fab60dc3c523b396af1") and Set Name to John But it's updating in all array2's first element's name to John.
db.getCollection('tests')
.updateOne({ "array1.array2._id": ObjectId("627a6fab60dc3c523b396af1") },{ $set: { "array1.$[].array2.$.name" : "John" } })
{
"_id" : ObjectId("627a6fab60dc3c523b396aec"),
"array1" : [
{
"array2" : [
{
"_id" : ObjectId("627a6fab60dc3c523b396af1"),
"name" : "test"
},
{
"_id" : ObjectId("627a6fab60dc3c523b396af2"),
"name" : "ABC"
}
],
"_id" : ObjectId("627a6fab60dc3c523b396aed")
},
{
"array2" : [
{
"_id" : ObjectId("627a6fab60dc3c523b396af3"),
"name" : "XYZ"
},
{
"_id" : ObjectId("627a6fab60dc3c523b396af4"),
"name" : "Testing"
}
],
"_id" : ObjectId("627a6fab60dc3c523b396aee")
}
]
}
Based on this great answer by #R2D2, you can do:
db.collection.update({
"array1.array2._id": ObjectId("627a6fab60dc3c523b396af1")
},
{
$set: {
"array1.$[].array2.$[y].name": "John"
}
},
{
arrayFilters: [
{
"y._id": ObjectId("627a6fab60dc3c523b396af1")
}
]
})
As you can see on this playground example
Trying to run an update call on mongoDB, but when I try and do so, said database isn't updated. Any help here?
The database doc we are trying to edit is in the form of:
{ "_id" : ObjectId("56d5f7eb604eb380b0d8d8dd"), "student_id" : 1, "scores" : [ { "type" : "exam", "score" : 79.51115675153915 }, { "type" : "quiz", "score" : 93.5960500282434 }, { "type" : "homework", "score" : 10.051101066555079 }, { "type" : "homework", "score" : 17.8164864139428 } ], "class_id" : 176 }
And the command being run is:
db.grades.update
(
{
$and:
[
{"class_id": 176},
{"student_id": 1}
]
},
{
$push:
{
scores:
{
"type": "extra credit",
"score": 10
}
}
}
)
Any help is appreciated!
I have a collection, consist of name and data.
data is an array with 2 elements, each element is the object with code and qty.
{
"_id" : ObjectId("605c666a15d2612ed0afedd2"),
"name" : "Anna",
"data" : [
{
"code" : "a",
"qty" : 3
},
{
"code" : "b",
"qty" : 4
}
]
},
{
"_id" : ObjectId("605c666a15d2612ed0afedd3"),
"name" : "James",
"data" : [
{
"code" : "c",
"qty" : 5
},
{
"code" : "d",
"qty" : 6
}
]
}
I want to update the code of the first element to name of its document. The result I want is
{
"_id" : ObjectId("605c666a15d2612ed0afedd2"),
"name" : "Anna",
"data" : [
{
"code" : "Anna",
"qty" : 3
},
{
"code" : "b",
"qty" : 4
}
]
},
{
"_id" : ObjectId("605c666a15d2612ed0afedd3"),
"name" : "James",
"data" : [
{
"code" : "James",
"qty" : 5
},
{
"code" : "d",
"qty" : 6
}
]
}
I just google to find how to:
update array at a specific index (https://stackoverflow.com/a/34177929/11738185)
db.Collection.updateMany(
{ },
{
$set:{
'data.0.code': '$name'
}
}
)
But the code of the first element in data array is a string '$name', not a value (Anna, James)
{
"_id" : ObjectId("605c666a15d2612ed0afedd2"),
"name" : "Anna",
"data" : [
{
"code" : "$name",
"qty" : 3
},
{
"code" : "b",
"qty" : 4
}
]
},
{
"_id" : ObjectId("605c666a15d2612ed0afedd3"),
"name" : "James",
"data" : [
{
"code" : "$name",
"qty" : 5
},
{
"code" : "d",
"qty" : 6
}
]
}
update a field by the value of another field. It takes me to use pipeline updating (https://stackoverflow.com/a/37280419/11738185): the second param of updateMany is array (pipeline)
db.Collection.updateMany(
{ },
[{
$set:{
'data.0.code': '$name'
}
}]
)
and It adds field 0 to each element in data array
{
"_id" : ObjectId("605c666a15d2612ed0afedd2"),
"name" : "Anna",
"data" : [
{
"0" : {
"code" : "Anna"
},
"code" : "a",
"qty" : 3
},
{
"0" : {
"code" : "Anna"
},
"code" : "b",
"qty" : 4
}
]
},
{
"_id" : ObjectId("605c666a15d2612ed0afedd3"),
"name" : "James",
"data" : [
{
"0" : {
"code" : "James"
},
"code" : "c",
"qty" : 5
},
{
"0" : {
"code" : "James"
},
"code" : "d",
"qty" : 6
}
]
}
I can't find the solution for this case. Could anyone to help me? How can I update array at fixed index by other field. Thanks for reading!
1. update array at a specific index
You can't use internal fields as value of another fields, it will work only when you have external value to update like { $set: { "data.0.code": "Anna" } }.
2. update a field by the value of another field
Update with Aggregation pipeline can't allow to access data.0.code syntax.
You can try using $reduce in update with aggregation pipeline,
$reduce to iterate loop of data array, set empty array in initialValue of reduce, Check condition if initialValue array size is zero then replace code with name and merge with current object using $mergeObjects, else return current object,
$concatArrays to concat current object with initialValue array
db.collection.update({},
[{
$set: {
data: {
$reduce: {
input: "$data",
initialValue: [],
in: {
$concatArrays: [
"$$value",
[
{
$cond: [
{ $eq: [{ $size: "$$value" }, 0] },
{ $mergeObjects: ["$$this", { code: "$name" }] },
"$$this"
]
}
]
]
}
}
}
}
}],
{ multi: true }
)
Playground
I think easier would be another way.
Just save the model before and use it for updating after
var annaModel = nameModel.findOne({_id: "605c666a15d2612ed0afedd2" })
nameModel.findOneAndUpdate({_id: "605c666a15d2612ed0afedd2"},{$set:{'data.0.code': annaModel.name}})
The data is like this:
{
"_id" : ObjectId("5ae9f2188857ce20f516315c"),
"meta" : {
"participants" : [
{
"gender" : [
{
"text" : "weiblich",
"id" : "LABEL.FEMALE"
}
]
},
{
"gender" : [
{
"text" : "männlich",
"id" : "LABEL.MALE"
}
]
},
{
"gender" : [
{
"text" : "weiblich",
"id" : "LABEL.FEMALE"
}
]
}
]
}
}
{
"_id" : ObjectId("5af00e1070bb5a707634cb12"),
"meta" : {
"participants" : [
{
"gender" : [
{
"text" : "männlich",
"id" : "LABEL.MALE"
}
]
},
{
"gender" : [
{
"text" : "männlich",
"id" : "LABEL.MALE"
}
]
}
]
}
}
{
"_id" : ObjectId("5af1ef01cfd317006694a6e6"),
"meta" : {
"participants" : [
{
"gender" : [
{
"text" : "weiblich",
"id" : "LABEL.FEMALE"
}
]
},
{
"gender" : [
{
"text" : "weiblich",
"id" : "LABEL.FEMALE"
}
]
}
]
}
}
So meta.participants contains some items with different properties e.g. gender with is also an array of one item (don't ask, historic reasons; it's always one item, never two and never empty).
I need a query which returns the documents which contains only male participants (the second doc 5af00e1070bb5a707634cb12).
I already tried my luck but I can't get it right.
These queries give me every doc which has a male participant:
{'meta.participants.gender.id': 'LABEL.MALE'}
{'meta.participants.gender': { $elemMatch: {id: 'LABEL.MALE'}}}
These queries give me 0 results..
{'meta.participants.gender': {id: 'LABEL.MALE'}}
{'meta.participants.gender[0]': { $elemMatch: {id: 'LABEL.MALE'}}}
Try the below:
db.collection.find({
"meta.participants": {
"$not": {
"$elemMatch": {
"gender.id": {
"$nin": [
"LABEL.MALE"
]
}
}
}
}
})
The query to retrieve documents with gender.id field do not have LABEL.FEMALE.
db.test.find( { "meta.participants.gender.id": { $ne: "LABEL.FEMALE" } } )
As such you don't need to use the $elemMatch for Single Query Condition (but, it not an error and the results will be same).