Related
I want to filter a nested object array by a field in mongoDb Compass.
Here is an example collection.
{
"_id": "MENU_ORDER_POS_1",
"menuVersion": "MENU_ORDER",
"menuType": "MAIN",
"status": "ENABLED",
"children": [
{
"_id": "MENU_ORDER_CHILD_1",
"menuVersion": "MENU_ORDER",
"status": "ENABLED",
"children": [
{
"_id": "MENU_ORDER_CHILD_1.1",
"menuVersion": "MENU_ORDER",
"status": "ENABLED",
"children": []
},
{
"_id": "MENU_ORDER_CHILD_1.2",
"menuVersion": "MENU_ORDER",
"status": "DISABLED",
"children": []
}
]
},
{
"_id": "MENU_ORDER_CHILD_2",
"menuVersion": "MENU_ORDER",
"status": "DISABLED",
"children": []
},
{
"_id": "MENU_ORDER_CHILD_3",
"menuVersion": "MENU_ORDER",
"status": "DISABLED",
"children": []
}
]
},
{
"_id": "MENU_ORDER_POS_2",
"menuVersion": "PANEL",
"menuType": "",
"defaultPath": "",
"eventNameToNavigate": "",
"status": "ENABLED",
"children": []
}
Expected output:
{
"_id": "MENU_ORDER_POS_1",
"menuVersion": "MENU_ORDER",
"menuType": "MAIN",
"status": "ENABLED",
"children": [
{
"_id": "MENU_ORDER_CHILD_1",
"menuVersion": "MENU_ORDER",
"status": "ENABLED",
"children": [
{
"_id": "MENU_ORDER_CHILD_1.1",
"menuVersion": "MENU_ORDER",
"status": "ENABLED",
"children": []
}
]
}
]
}
Aggregate stages
First I need to get all the documents with menuVersion = "MENU_ORDER" and status = "ENABLED".
Then I need to filter all nested items in the children Array, note that this array is recursive and can have multiple children object inside an item. I need to get all the children items that matches status = "ENABLED"
Note The children array can have elements with the children object and this can be infinite, it is multilevel and all the items in the nested array must meet the filter criteria
I figure aggregate is the best choice here, using match and filter should do the job but I can't figure how to make it infinite recursive to filter all N child in the array.
So far I have written the filter part.
{
children: {
$filter: {
input: "$children",
as: "children",
cond: {
$eq: "children.status", "ENABLED" }
}
}
}
Your approach of using $filter is correct. You just need to refer the variable you set (i.e. children) using $$. Repeat it again with the inner array.
db.collection.aggregate([
{
$set: {
children: {
"$filter": {
"input": "$children",
"as": "c",
"cond": {
$and: [
{
$eq: [
"$$c.menuVersion",
"MENU_ORDER"
]
},
{
$eq: [
"$$c.status",
"ENABLED"
]
}
]
}
}
}
}
},
{
$set: {
children: {
"$map": {
"input": "$children",
"as": "c",
"in": {
"$mergeObjects": [
"$$c",
{
"children": {
"$filter": {
"input": "$$c.children",
"as": "innerChild",
"cond": {
$eq: [
"$$innerChild.status",
"ENABLED"
]
}
}
}
}
]
}
}
}
}
}
])
Mongo Playground
I'm a mongo beginner and struggling to insert multiple objects into multiple nested array in one document.
The document looks like this:
[
{
"id": 1,
"name": "myObject",
"sections": [
{
"id": "section1",
"items": [
{
"id": 1,
"name": "item1.1",
"scores": [
{
"userId": 13,
"score": 10
}
]
},
{
"id": 2,
"name": "item1.2",
"scores": [
{
"userId": 66,
"score": 10
}
]
}
]
},
{
"id": "section2",
"items": [
{
"id": 3,
"name": "item2.1",
"scores": [
{
"userId": 13,
"score": 20
}
]
}
]
}
]
}
]
I now want to insert new scores for userId=10 for every item in every section.
The score is of course different for every item.
let's assume scores like this (all for userId=10)
[
{
"sectionId": "section1"
"itemName: "item1.1"
"score: 10,
"userId": 10
},
{
"sectionId": "section1"
"itemName: "item1.2"
"score: 15,
"userId": 10
},
{
"sectionId": "section2"
"itemName: "item2.1"
"score: 33,
"userId": 10
}
]
Added for clarification
the updated document should look like the following.
{
"id": 1,
"name": "myObject",
"sections": [
{
"id": "section1",
"items": [
{
"id": 1,
"name": "item1.1",
"scores": [
{
"userId": 13,
"score": 10
},
{ // <-- newly added score
"userId": 10,
"score": 10
}
]
},
{
"id": 2,
"name": "item1.2",
"scores": [
{
"userId": 66,
"score": 10
},
{ // <- newly added score
"userId": 10,
"score": 15
}
]
}
]
}
// the remaining document is omitted for brevity but the above should also be applied to this sections
so far I have been able to achieve what I want for one single score like this
db.collection.update({
id: 1
},
{
$push: {
"sections.$[item].items.$[score].scores": {
"userId": 10,
"score": 13
},
}
},
{
arrayFilters: [
{
"score.userId": {
$ne: 10
}
},
{
"item.name": {
$eq: "item1.1"
}
}
]
})
This inserts a score for userId=10 in itemName=item1.1 if no score for userId=10 exists.
But I'm struggling on how to insert multiple scores into multiple items.
I saw that you can merge objects together, so maybe this would be an option although it kinda fells like an overkill.
So how can I insert all my scores for the different items in one atomic operation?
EDIT: Added clarification about the desired result.
Query
pipeline update, requires MongoDB >= 4.2
reduce on the data that you want to insert, with initial value the sections
nested 3 maps that always do the same
if its not the key-value i want, keep the old value
else (merge {:newkey (map ...)})
if userId exists updates its score, else insert new userID and score
query assumes that there is a score array even if empty, i mean it
only creates new userId+score, not sections items etc
*you can avoid the set/unset and use driver variables in all the places where data is used
PlayMongo
db.collection.update({},
[
{
"$set": {
"data": [
{
"sectionId": "section1",
"itemName": "item1.1",
"userId": 10,
"score": 20
},
{
"sectionId": "section1",
"itemName": "item1.1",
"userId": 13,
"score": 30
},
{
"sectionId": "section2",
"itemName": "item2.1",
"score": 33,
"userId": 10
}
]
}
},
{
"$set": {
"sections": {
"$reduce": {
"input": "$data",
"initialValue": "$sections",
"in": {
"$let": {
"vars": {
"data": "$$this"
},
"in": {
"$map": {
"input": "$$value",
"in": {
"$cond": [
{
"$ne": [
"$$section.id",
"$$data.sectionId"
]
},
"$$section",
{
"$mergeObjects": [
"$$section",
{
"items": {
"$map": {
"input": "$$section.items",
"in": {
"$cond": [
{
"$ne": [
"$$item.name",
"$$data.itemName"
]
},
"$$item",
{
"$mergeObjects": [
"$$item",
{
"scores": {
"$let": {
"vars": {
"user_exist": {
"$in": [
"$$data.userId",
"$$item.scores.userId"
]
}
},
"in": {
"$cond": [
{
"$not": [
"$$user_exist"
]
},
{
"$concatArrays": [
"$$item.scores",
[
{
"userId": "$$data.userId",
"score": "$$data.score"
}
]
]
},
{
"$map": {
"input": "$$item.scores",
"in": {
"$cond": [
{
"$ne": [
"$$score.userId",
"$$data.userId"
]
},
"$$score",
{
"$mergeObjects": [
"$$score",
{
"score": "$$data.score"
}
]
}
]
},
"as": "score"
}
}
]
}
}
}
}
]
}
]
},
"as": "item"
}
}
}
]
}
]
},
"as": "section"
}
}
}
}
}
}
}
},
{
"$unset": [
"data"
]
}
])
My data looks something like that:
[
{
"_id": 1,
"members": [
{
"id": 1,
"name": "name_1",
"assigned_tasks": [
1,
2,
3
]
},
{
"id": 1,
"name": "name_2",
"assigned_tasks": [
1
]
}
],
"tasks": [
{
"id": 1,
"name": "task_1",
},
{
"id": 2,
"name": "task_2",
},
{
"id": 3,
"name": "task_3",
}
]
}
]
I have a collection that represents a "class" which contains a list of members and a list of projects.
Each member can be assigned to multiple projects.
I wanna be able to count the number of members assigned to each of the tasks in the results and add it as a new field like:
[
{
"_id": 1,
"members": [
{
"id": 1,
"name": "name_1",
"assigned_tasks": [
1,
2,
3
]
},
{
"id": 1,
"name": "name_2",
"assigned_tasks": [
1
]
}
],
"tasks": [
{
"id": 1,
"name": "task_1",
"number_of_assigned_members":2
},
{
"id": 2,
"name": "task_2",
"number_of_assigned_members":1
},
{
"id": 3,
"name": "task_3",
"number_of_assigned_members":2
}
]
}
]
How can I create that query?
You can use $map and than $reduce,
$map tasks through object by object check in $reduce on members, if assigned_tasks is available or not, if available then add 1 otherwise 0,
db.collection.aggregate([
{
$addFields: {
tasks: {
$map: {
input: "$tasks",
as: "t",
in: {
$mergeObjects: [
"$$t",
{
number_of_assigned_members: {
$reduce: {
input: "$members",
initialValue: 0,
in: {
$cond: [
{ $in: ["$$t.id", "$$this.assigned_tasks"] },
{ $add: ["$$value", 1] },
"$$value"
]
}
}
}
}
]
}
}
}
}
}
])
Playground
Let's consider that I have the following documents (ignoring the _id):
[
{
"Id": "Store1",
"Info": {
"Location": "Store1 Street",
"PhoneNumber": 111
},
"MaxItemsPerShelf": 3,
"Shelf": [
{
"Id": "Shelf1",
"Items": [
{
"Id": "Item1",
"Name": "bananas"
},
{
"Id": "Item2",
"Name": "apples"
},
{
"Id": "Item3",
"Name": "oranges"
}
]
},
{
"Id": "Shelf2",
"Items": [
{
"Id": "Item4",
"Name": "cookies"
},
{
"Id": "Item5",
"Name": "chocolate"
}
]
},
{
"Id": "Shelf3",
"Items": []
}
]
},
{
"Id": "Store3",
"Info": {
"Location": "Store2 Street",
"PhoneNumber": 222
},
"MaxItemsPerShelf": 2,
"Shelf": [
{
"Id": "Shelf4",
"Items": [
{
"Id": "Item6",
"Name": "champoo"
},
{
"Id": "Item7",
"Name": "toothpaste"
}
]
},
{
"Id": "Shelf5",
"Items": [
{
"Id": "Item8",
"Name": "chicken"
}
]
}
]
}
]
Given a specific Shelf.Id I want to get the following result ( Shelf.Id = "Shelf2"):
[{
"Info": {
"Location": "Store1 Street",
"PhoneNumber": 111
},
"ItemsNumber": 2,
"ItemsRemaining": 1
}]
Therefore:
ItemsNumberis the $size of Shelf
and
ItemsRemainingis equal to MaxItemsPerShelf $size of Shelf
also I want to copy the value of the Info to the aggregate output.
How can I accomplish this with aggregate? On my efforts I couldn't pass through an iterator that gets the $size of $Shelf.Items
You can use below aggregation
db.collection.aggregate([
{ "$match": { "Shelf.Id": "Shelf2" }},
{ "$replaceRoot": {
"newRoot": {
"$let": {
"vars": {
"shelf": {
"$filter": {
"input": {
"$map": {
"input": "$Shelf",
"in": {
"Id": "$$this.Id",
"count": { "$size": "$$this.Items" }
}
}
},
"as": "ss",
"cond": { "$eq": ["$$ss.Id", "Shelf2"] }
}
}
},
"in": {
"Info": "$Info",
"ItemsNumber": { "$arrayElemAt": ["$$shelf.count", 0] },
"ItemsRemaining": {
"$subtract": [
"$MaxItemsPerShelf",
{ "$ifNull": [
{ "$arrayElemAt": ["$$shelf.count", 0] },
0
]}
]
}
}
}
}
}}
])
How to populate in result of aggregated query in monogdb
Array of followedId
var followeduserId = ["abc","efg","xyz","pqr","acd","rts"];
Feeds Recommended
[
{
"feedsId": "feed1",
"userId": "abc"
},
{
"feedsId": "feed1",
"userId": "efg"
}
]
Feeds collection
[
{
"link": "www.yodo.com",
"recommended": [
"abc",
"efg"
],
"title": "This is my feed7",
"topics": [
"topi1",
"topi2",
"topi3",
"topi4"
]
},
{
"link": "www.yodo.com",
"recommended": [
"abc",
"efg",
"das",
"asd",
"eqw",
"weq"
],
"title": "This is my feed8",
"topics": [
"topi1",
"topi2",
"topi3",
"topi4"
]
}
]
Ran aggregation query
feedsrecommended.aggregate([
{ $match: { userId: { $in: "followersId" }}},
{ $lookup: {
from: "feeds",
localField: "feedsId",
foreignField: "_id",
as: "feedsId"
}},
{ $group: {
"_id": { "feedsId": "$feedsId" },
"count": { "$sum": 1 }
}},
{ $sort: { count: -1 }}
])
result After aggregation
var resultfeeds = [
{
"count": 7,
"id": {
"_id": "feed1",
"link": "www.yodo.com",
"recommended": [
"abc",
"efg",
"xyz",
"pqr",
"acd",
"rts"
],
"title": "This is my feed1",
"topics": [
"topi1",
"topi8",
"topi6",
"topi5"
]
}
},
{
"count": 3,
"id": {
"_id": "feed5",
"link": "www.yodo.com",
"recommended": [
"abc",
"efg",
"acd",
"rts"
],
"title": "This is my feed1",
"topics": [
"topi1",
"topi2",
"topi3",
"topi4"
]
}
},
{
"count": 3,
"id": {
"_id": "feed6",
"link": "www.yodo.com",
"recommended": [
"abc",
"efg",
"xyz",
"pqr"
],
"title": "This is my feed1",
"topics": [
"topi7",
"topi1",
"topi4",
"topi8"
]
}
},
{
"count": 2,
"id": {
"_id": "feed2",
"link": "www.yodo.com",
"recommended": [
"abc",
"acd",
"rts"
],
"title": "This is my feed1",
"topics": [
"topi7",
"topi6",
"topi8"
]
}
},
{
"count": 2,
"id": {
"_id": "feed7",
"link": "www.yodo.com",
"recommended": [
"abc",
"efg"
],
"title": "This is my feed1",
"topics": [
"topi1",
"topi5",
"topi6",
"topi4"
]
}
},
{
"count": 1,
"id": {
"_id": "feed3",
"link": "www.yodo.com",
"recommended": [
"abc",
"asd",
"eqw",
"weq"
],
"title": "This is my feed1",
"topics": [
"topi1",
"topi7",
"topi6",
"topi4"
]
}
},
{
"count": 1,
"id": {
"_id": "feed8",
"link": "www.yodo.com",
"recommended": [
"abc",
"das",
"asd",
"eqw",
"weq"
],
"title": "This is my feed1",
"topics": [
"topi1",
"topi2",
"topi5",
"topi4"
]
}
}
]
I want to populate topics and recommeded userName and image in the result
topic collection
[
{
"topic_name": "tiger"
},
{
"topic_name": "loin"
}
]
user collection
[
{
"name": "deepa",
"profileImg": "www.com/facebook.jpg"
},
{
"name": "nisa",
"profileImg": "www.com/facebook.jpg"
}
]
My last result should be like this
[
{
"count": 2,
"id": {
"_id": "feed2",
"link": "www.yodo.com",
"recommended": [
{
"_id": "abc",
"name": "deepa",
"profileImg": "www.com/facebook.jpg"
},
{
"_id": "acd",
"name": "sigger",
"profileImg": "www.com/facebook.jpg"
},
{
"_id": "rts",
"name": "buster",
"profileImg": "www.com/facebook.jpg"
}
],
"title": "This is my feed1",
"topics": [
{
"_id": "topi6",
"topic_name": "boolena"
},
{
"_id": "topi7",
"topic_name": "mika"
},
{
"_id": "topi8",
"topic_name": "tika"
}
]
}
}
]
You can try below aggregation in mongodb 3.6 and above
Feedsrecommended.aggregate([
{ "$match": { "userId":{ "$in": followersId }}},
{ "$group": {
"_id": "$feedsId",
"count": { "$sum": 1 }
}},
{ "$lookup": {
"from": "feeds",
"let": { "feedsId": "$_id" },
"pipeline": [
{ "$match": { "$expr": { "$eq": [ "$_id", "$$feedsId" ] }}},
{ "$lookup": {
"from": "topics",
"let": { "topics": "$topics" },
"pipeline": [
{ "$match": { "$expr": { "$in": [ "$_id", "$$topics" ] } } }
],
"as": "topics"
}},
{ "$lookup": {
"from": "users",
"let": { "recommended": "$recommended" },
"pipeline": [
{ "$match": { "$expr": { "$in": [ "$_id", "$$recommended" ] } } }
],
"as": "recommended"
}}
],
"as": "feedsId"
}}
])