$match in aggregate don't return data in mongodb - mongodb

Question

I have three tables below is the structure like below
I'm looking to get a result like below
"type1": [ -- type from Accounts collection
{
"_id": "5e97e9a224f62f93d5x3zz46", -- _id from Accounts collection
"locs": "sampleLocks 1", -- field from Accounts collection
"solutions": "sample solutions 1", -- field from Accounts collection
"Clause": "clause 1" -- field from AccountsDesc collection
},
{
"_id": "5e97e9a884f62f93d5x3zz46",
"locs": "sampleLocks2",
"solutions": "sample solutions2",
"Clause": "clause2"
}
],
"type2": [
// same data construction as of type1 above
]
_id, locks, solution to be coming from Accounts collection
Clause field to be coming from AccountsDesc collection
accounts_id is kind of a foreign key in AccountsDesc coming from Account
competitor_id is kind of a foreign key in AccountsDesc coming from Competitor
Below is what my query looks like
db.accountDesc.aggregate([
{
$match : {accounts_Id : "123456"}, active: true}
},
{
$lookup: {
from: 'accounts',
pipeline: [{ $match: { type: { $in: ["type1, type2, type3"] } } }],
as: 'accountsData'
}
},
{
$group: {
_id: "$accountsData.type",
data: {
$push: {_id: "$accountsData._id", clause: "$clause", locs: "$type.locs", solutions: "$type.solutions"}
}
}
},
{
$group: {
_id: null,
data: {
$push: {
k: {
$toString: '$_id'
},
v: '$data'
}
}
}
},
{
$replaceRoot: {
newRoot: {
$arrayToObject: '$data'
}
}
}
])
Issues related with the query -
$match : {accountId : "123456"}, active: true} -- No data is returned if i use match on AccountsDesc collection
cant set localField, foriegnField if im using pipeline, then how the mapping will happen like a LEFT join.
clause: "$clause" don't get the value of this field in the response

Answer 1

As we discussed in chat, you want RIGHT OUTER JOIN for your aggregation.
Try the query below:
db.User_Promo_Map.aggregate([
{
$match: {
user_Id: ObjectId("5e8c1180d59de1704ce68112")
}
},
{
$lookup: {
from: "promo",
pipeline: [
{
$match: {
active: true,
platform: {
$in: [
"twitch",
"youtube",
"facebook"
]
}
}
}
],
as: "accountsData"
}
},
{
$unwind: "$accountsData"
},
{
$group: {
_id: "$accountsData.platform",
data2: {
$addToSet: {
amount: "$amount",
promo_Id: "$promo_Id"
}
},
data: {
$addToSet: {
_id: "$accountsData._id",
format: "$accountsData.format",
description: "$accountsData.description"
}
}
}
},
{
$addFields: {
data: {
$map: {
input: "$data",
as: "data",
in: {
"_id": "$$data._id",
"description": "$$data.description",
"format": "$$data.format",
amount: {
$reduce: {
input: "$data2",
initialValue: "$$REMOVE",
in: {
$cond: [
{
$eq: [
"$$this.promo_Id",
"$$data._id"
]
},
"$$this.amount",
"$$value"
]
}
}
}
}
}
}
}
},
{
$group: {
_id: null,
data: {
$push: {
k: {
$toString: "$_id"
},
v: "$data"
}
}
}
},
{
$replaceRoot: {
newRoot: {
$arrayToObject: "$data"
}
}
}
])
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