using match for both linked collection of mongo in lookup - mongodb

Question

I have two collections - orders, feedback
Orders:
{
"restaurantId" : NumberInt(138),
"referenceNo" : "1980DBF5",
"orderId" : "1045593",
"userId" : NumberInt(6664960),
"userEmail" : "user#g.com",
"firstName" : "User"
}
Feedbacks:
{
"rating" : NumberInt(4),
"additionalComments" : "it is working",
"referenceNo" : "7D02097F",
"productId" : NumberInt(1),
"restaurantId" : NumberInt(138),
"orderType" : "1"
}
I need to make a join on these two collections.
Also, there will be filter inputs on rating, referenceNo, userEmail, firstName.
How can I use match to get data from two collections?
This is my aggregate query:
[
{
"$lookup":
{
"from": "orders",
"localField": "referenceNo",
"foreignField": "referenceNo",
"as": "data"
}
}
]
I am using this query on feedback model.
The data that I get is:
{
"rating" : NumberInt(4),
"additionalComments" : "it is working",
"referenceNo" : "7D02097F",
"productId" : NumberInt(1),
"restaurantId" : NumberInt(138),
"orderType" : "1"
"data": [{
"restaurantId" : NumberInt(138),
"referenceNo" : "1980DBF5",
"orderId" : "1045593",
"userId" : NumberInt(6664960),
"userEmail" : "user#g.com",
"firstName" : "User"
}]
}
Also, would it be possible to add limits here?
Earlier I was using this on orders -
mQuery.skip(Number(paginate.offset)).limit(Number(paginate.limit));

Answer 1

Check if this helps....
db.feedbacks.aggregate([ {
$lookup:
{
from: "users",
localField: "whatever",
foreignField: "whatever",
as: "data"
}},
{
$unwind: "$data"
},
{
$match:
{
"data.orderId":"1045593"} //conditions
},
{
$limit:1 //limit
}
]);