i new in MongoDB and i have a documment in mongo with this structure:
{
"game" : "chess",
"name" : "Chess",
"prizes" : [
{
"_id" : ObjectId("562575c61d41c81efce7bc1b"),
"group" : 0,
"name" : "10 coins",
"pos" : "0",
},
{
"_id" : ObjectId("562575c61d41c81efce7bc1c"),
"group" : 0,
"name" : "10 coins",
"pos" : "1",
},
{
"_id" : ObjectId("562575c61d41c81efce7bc1d"),
"group" : 1,
"name" : "20 coins",
"pos" : "2",
},
}
I need to get some like this:
{
"game" : "chess",
"name" : "Chess",
"prizes" : [
{
"name" : "10 coins",
"group" : 0,
},
{
"name" : "20 coins",
"group" : 1,
}
I try with aggregate and projection and unwind but i don't get the structure that i need, thanks.
Basically I'm unwinding and then getting the prizes array down to just the fields you want based on your questions desired output. then group them all together using the game and name and using $addToSet to insert unique entires of group and name into the array. Im making the assumption of no duplicate games but I think it would work anyway since they would just all get grouped in together.
db.docs.aggregate([
{$unwind : '$prizes'},
{$project: {name: '$name', game: '$game', prizes: {group: '$prizes.group', name: '$prizes.name'}}},
{$group: {_id: {name: '$name', game: '$game'}, prizes: {$addToSet: '$prizes'}}},
])
You can try like below. Use $map with some set operation $setUnion or $setDifference, only needed to filter duplicates while transforming the shape.
aggregate([{
"$project": {
"game": 1,
"name": 1,
"prizes": {
"$setUnion": [{
"$map": {
"input": "$prizes",
"as": "prize",
in: {
"name": "$$prize.name",
"group": "$$prize.group"
}
}
},
[]
]
}
}
}]).pretty();
Related
The problem: I'm trying to make a query on MongoDB, but I'm using the DocumentDb from amazon, where some operations are no supported. I wanted to find an alternative to get the same result, if possible. Basically I want to change the root of the result, instead of being the first entity, I need it to be some merging of some values in different levels of the document.
So, I have the following structure in my collection:
{
"_id" : ObjectId("5e598bf4d98f7c70f9aa3b58"),
"status" : "active",
"invoices" : [
{
"_id" : ObjectId("5e598bf13b24713f50600375"),
"value" : 1157.52,
"receivables" : [
{
"situation" : {
"status" : "active",
"reason" : []
},
"rec_code" : "001",
"_id" : ObjectId("5e598bf13b24713f50600374"),
"expiration_date" : ISODate("2020-03-25T00:00:00.000Z"),
"value" : 1157.52
}
],
"invoice_code" : 9773,
"buyer" : {
"legal_name" : "test name",
"buyer_code" : "223132165498797"
}
},
],
"seller" : {
"code" : "321654897986",
"name" : "test name 2"
}
}
What I want to achieve is to list all "receivables" like this, where the _id is the _id of the receivable:
[{
"_id" : ObjectId("5e598bf13b24713f50600374"),
"situation" : {
"status" : "active",
"reason" : []
},
"rec_code" : "001",
"expiration_date" : ISODate("2020-03-25T00:00:00.000Z"),
"value" : 1157.52,
"status" : "active",
"seller" : {
"cnpj" : "321654897986",
"name" : "test name 2"
},
"invoice_code" : 9773.0,
"buyer" : {
"legal_name" : "test name",
"cnpj" : "223132165498797"
}
}]
This I can do with $replaceRoot in with the query below on MongoDB, but using documentDB I can't use $replaceRoot or $mergeObjects. Do you know how can I get the same result with other operators?:
db.testCollection.aggregate([
{ $unwind: "$invoices" },
{ $replaceRoot: {
newRoot: {
$mergeObjects: ["$$ROOT","$invoices"]}
}
},
{$project: {"_id": 0, "value": 0, "created_at": 0, "situation": 0}},
{ $unwind: "$receivables" },
{ $replaceRoot: {
newRoot: {
$mergeObjects: ["$receivables", "$$ROOT"]
}
}
},
{$project:{"created_at": 0, "receivables": 0, "invoices": 0}}
])
After going through mongodb operations, I could get a similar result fro what I wanted with the following query without $replaceRoot. It turns out it was a better query, I think:
db.testCollection.aggregate([
{$unwind: "$invoices"},
{$project : {
created_at: 1,
seller: "$seller",
buyer: "$invoices.buyer",
nnf: "$invoices.nnf",
receivable: '$invoices.receivables'
}
},
{$unwind: "$receivable"},
{$project : {
_id: '$receivable._id',
seller: 1,
buyer: 1,
invoice_code: 1,
receivable: 1,
created_at: 1,
}
},
{$sort: {"created_at": -1}},
])
This query resulted in the following structure list:
[{
"created_at" : ISODate("2020-03-06T09:47:26.161Z"),
"seller" : {
"name" : "Test name",
"cnpj" : "21231232131232"
},
"buyer" : {
"cnpj" : "21322132164654",
"legal_name" : "Test name 2"
},
"invoice_code" : 66119,
"receivable" : {
"rec_code" : "001",
"_id" : ObjectId("5e601bb5efff82b92935bad4"),
"expiration_date" : ISODate("2020-03-17T00:00:00.000Z"),
"value" : 6540.7,
"situation" : {
"status" : "active",
"reason" : []
}
},
"_id" : ObjectId("5e601bb5efff82b92935bad4")
}]
Support for $replaceRoot was added to Amazon DocumentDB in January 2021.
I have a customers collection such as;
{
"_id" : ObjectId("5de8c07dc035532b489b2e23"),
"name" : "sam",
"orders" : [{"ordername" : "cola"},{"ordername" : "cheesecake"}]
}
And waiters collection such as;
{
"_id" : ObjectId("5de8bc24c035532b489b2e20"),
"waiter" : "jack",
"products" : [{"name" : "cola", "price" : "4"},
{"name" : "water", "price" : "2"},
{"name" : "coffee", "price" : "8" }]
}
{
"_id" : ObjectId("5de8bdc7c035532b489b2e21"),
"waiter" : "susan",
"products" : [{"name" : "cheesecake", "price" : "12" },
{"name" : "apple pie", "price" : "14" }]
}
I want to join the objects from waiters collection into the customers collection by matching "products.name" and "orders.ordername". But, the result includes the whole document from the waiters collection, however, I want only the matched objects inside the document. Here is what I want;
ordered:[
{"name" : "cola", "price" : "4"},
{"name" : "cheesecake", "price" : "12" },
]
I tried $lookup with and without pipeline, and filter but could not get this result. Thanks in advance.
You had the right idea, we just have to "massage" the data a bit due to its structure like so:
db.collection.aggregate([
{
$addFields: {
"orderNames":
{
$reduce: {
input: "$orders",
initialValue: [],
in: {$concatArrays: [["$$this.ordername"], "$$value"]}
}
}
}
},
{
$lookup:
{
from: "waiters",
let: {orders: "$orderNames"},
pipeline: [
{
$unwind: "$products"
},
{
$match:
{
$expr:{$in: ["$products.name", "$$orders"]},
}
},
{
$group: {
_id: "$products.name",
price: {$first: "$products.price"}
}
},
{
$project: {
_id: 0,
price: 1,
name: "$_id"
}
}
],
as: "ordered"
}
}
])
It feels like you could benefit from a new collection of mapping items to prices. Could potentially save you a lot of time.
I'm learning MongoDB's sorting. I have a collection with documents that look like this:
{
"_id" : ObjectId("5d0c13fbfdca455311248d6f"),
"borough" : "Brooklyn",
"grades" :
[
{ "date" : ISODate("2014-04-16T00:00:00Z"), "grade" : "A", "score" : 5 },
{ "date" : ISODate("2013-04-23T00:00:00Z"), "grade" : "B", "score" : 2 },
{ "date" : ISODate("2012-04-24T00:00:00Z"), "grade" : "A", "score" : 4 }
],
"name" : "C & C Catering Service",
"restaurant_id" : "40357437"
}
And I want to sort all restaurants in Brooklyn by their most recent score.
Right now I have:
db.restaurants.find({borough: "Brooklyn"}).sort()
But I don't know how to proceed. Any help on how to sort this by most recent score, which is the first entry in grades?
This is not possible in mongo with a find query, you'll have to use an aggregation like this one:
db.collection.aggregate([
{
$unwind: "$grades"
},
{
$sort: {"grades.date": -1}
},
{
$group: {
_id:"$_id",
grades: {$push:"$grades"},
resturant_id: {$first: "$resturant_id",
name: {$first: "$name"},
borough: {$first: "$borough"}
}
}
]);
EDIT:
collection.find({}).sort({'grades.0.date': -1});
I have this simple Mongodb document:
{
"_id" : ObjectId("55663d9361cfa81a5c48d54f")
"name" : "Oliver",
"surname" : "Queen",
"age" : 25,
"friends" : [
{
"name" : "Jhon",
"surname" : "Diggle",
"age" : "30"
},
{
"name" : "Barry",
"surname" : "Allen",
"age" : "24"
}
]
}
Is it possbile, using denormalized model as above, to find all Oliver's friends with 24 years old?
I think it's really simple with normalized model; it's enough to do two queries.
For example the following query:
db.collection.find({name:"Oliver", "friends.age":24}, {_id:0, friends:1})
returns an array of Oliver's friends. Is it possible to make a selection of the internal document?
Using aggregation
db.collection.aggregate(
[
{ $match: { "name": "Oliver" }},
{ $unwind: "$friends" },
{ $match: { "friends.age": 24 }},
{ $group: { "_id": "$_id", friends: { "$push": "$friends" }}},
{ $project: { "_id": 0, "friends": 1 }}
]
)
I have a collection that has records looking like this:
"_id" : ObjectId("550424ef2f44472856286d56"), "accountId" : "123",
"contactOperations" :
[
{ "contactId" : "1", "operation" : 1, "date" : 500 },
{ "contactId" : "1", "operation" : 2, "date" : 501 },
{ "contactId" : "2", "operation" : 1, "date" : 502 }
]
}
I want to know the latest operation number that has been applied on a certain contact.
I'm using the aggregation framework to first unwind the contactOperations and then grouping by accountId and contactOperations.contactId and max contactOperations.date.
aggregate([{$unwind : "$contactOperations"}, {$group : {"_id":{"accountId":"$accountId", "contactId":"$contactOperations.contactId"}, "date":{$max:"$contactOperations.date"} }}])
The result I get is:
"_id" : { "accountId" : "123", "contactId" : "2" }, "time" : 502 }
"_id" : { "accountId" : "123", "contactId" : "1" }, "time" : 501 }
Which seems correct so far, but I also need the contactOperations.operation field that was recorded with $max date. How can I select that?
You have to sort the unwind values then apply $last operator to get operation for max date. Hope this query will solve your problem.
aggregate([
{
$unwind: "$contactOperations"
},
{
$sort: {
"date": 1
}
},
{
$group: {
"_id": {
"accountId": "$accountId",
"contactId": "$contactOperations.contactId"
},
"date": {
$max: "$contactOperations.date"
},
"operationId": {
$last: "$contactOperations.operation"
}
}
}
])