I'm quite new on MongoDB
Having a document like:
"_id":0001
"Name": "John"
"Contacts": [
{
"Person" : [
{
"User" : {
"_id" : ObjectId("5836b916885383034437d230"),
"Name": "Name1",
"Age" : 25,
}
},
{
"User" : {
"_id" : ObjectId("2836b916885383034437d230"),
"Name": "Name2",
"Age" : 30,
}
},
{
"User" : {
"_id" : ObjectId("1835b916885383034437d230"),
"Name": "Name3",
"Age" : 31,
}
},
}
which is the best way to get an output with the information of the Contacts with age greater or equal than 30 years?
Output should like:
{_id: "John", "ContactName":"Name2", "Age":30 }
{_id: "John", "ContactName":"Name3", "Age":31 }
Is aggregation the best way to do it, or it can be done by using a simple "find" statement?
$match
$unwind
$unwind
$match
$project
db.collection.aggregate([
{
"$match": {
"Contacts.Person.User.Age": {
"$gte": 30
}
}
},
{
"$unwind": "$Contacts"
},
{
"$unwind": "$Contacts.Person"
},
{
"$match": {
"Contacts.Person.User.Age": {
"$gte": 30
}
}
},
{
"$project": {
"_id": "$Name",
"ContactName": "$Contacts.Person.User.Name",
"Age": "$Contacts.Person.User.Age"
}
}
])
mongoplayground
Related
Hello I am new to mongoDB, please I hope you can help me with this question.
My collection will look like this:
{
"_id": { "$oid": "5f1fd47..." },
"email":"c#c.com",
"materials": [
{
"_id": { "$oid": "5f1fda2..." },
"title": "MDF 18mm Blanco",
"id": "mdf18blanco",
"thickness": "18",
"family": "MDF",
"color": ""
}, ...
//others materials with different family
],
}
I did an aggregate like this:
{ "$match" : { "email" : "c#c.com" } },
{ "$unwind" : "$materials" },
{ "$group" : { "_id" : "$_id", "list" : { "$push" : "$materials.family" } } }
and I return this:
{
"_id" : ObjectId("5f1fd47d502e00051c673dd1"),
"list" : [
"MDF",
"MDF",
"MDF",
"Melamina",
"Melamina",
"Melamina",
"Melamina",
"MDF",
"Melamina",
"Aglomerado",
"Aglomerado"
]
}
but i need get this
{
"_id" : ObjectId("5f1fd47d502e00051c673dd1"),
"list" : [
"MDF",
"Melamina",
"Aglomerado"
]
}
I hope you understand my question and can help me, thank you very much.
All you need to do is use $addToSet instead of $push in your group stage:
{ "$group" : { "_id" : "$_id", "list" : { "$addToSet" : "$materials.family" } } }
One thing to note is that $addToSet does not guarantee a specific order as opposed to $push in case it matters to you.
You only need change $push to $addToSet.
A set not contains repeat values so it works.
db.collection.aggregate([
{
"$match": {
"email": "c#c.com"
}
},
{
"$unwind": "$materials"
},
{
"$group": {
"_id": "$_id",
"list": {
"$addToSet": "$materials.family"
}
}
}
])
Mongo Playground example
This question already has answers here:
How to return just the nested documents of an array from all documents
(2 answers)
Closed 3 years ago.
I'm trying to deep query and retrieve specific fields from MongoDB, but unfortunately couldn't able to figure out the correct solution.
Document data:
[ {
"_id": 39127198,
"name": "Mike",
"details": {
"age": 25,
"vehicles":[
{"brand":"Chevrolet","model":"Silverado","plate":"AB11"},
{"brand":"Jeep","model":"Cherokee","plate":"CG678"}
]
}
}, {
"_id": 39127198,
"name": "Taylor",
"details": {
"age": 25,
"vehicles": [
{"brand":"GMC","model":"Sierra","plate":"748397"}
]
}
} ]
My requirement: Return "vehicles" array alone for a specific player. Let's say for user "Mike" in this case.
Here is what I tried;
collection.find( {"name":"Mike"} )
.project( {"details.vehicles" : 1, "_id": 0, "name": 0} )
.toArray(function(err, result) { ... } )
collection.aggregate([
{ $match: { "name":"Mike" } },
{ $project: {"details.vehicles" : 1, "_id": 0, "name": 0} }
]).toArray(function(err, result) { ... } )
Here is what I get for the above code:
[
{
"details": {
"vehicles": [
{"brand":"Chevrolet","model":"Silverado","plate":"AB11"},
{"brand":"Jeep","model":"Cherokee","plate":"CG678"}
]
}
}
]
Expected:
[
{"brand":"Chevrolet","model":"Silverado","plate":"AB11"},
{"brand":"Jeep","model":"Cherokee","plate":"CG678"}
]
I am using MongoClient. MongoDB shell version v4.2.1
You can use $unwind and $replaceRoot stages to achieve this :
db.collection.aggregate([
{
$match: {
"name": "Mike"
}
},
{
$unwind: "$details.vehicles"
},
{
$replaceRoot: {
newRoot: "$details.vehicles"
}
}
])
Will output exactly what you need.
Hope it helps
The query:
db.vehi.aggregate( [
{ $match: { "name":"Mike" } },
{ $project: { "vehicles": "$details.vehicles", "_id": 0 } }
] ).next().vehicles
The exact output:
[
{
"brand" : "Chevrolet",
"model" : "Silverado",
"plate" : "AB11"
},
{
"brand" : "Jeep",
"model" : "Cherokee",
"plate" : "CG678"
}
]
- OR -
This also gets the same result:
db.vehi.find(
{ "name" : "Mike" },
{ "details.vehicles" : 1, _id : 0 }
).next().details.vehicles
i have collection data like this -
{
"user_id" : "1",
"branch_id" : "1",
"total" : 100,
},
{
"user_id" : "1",
"branch_id" : "1",
"total" : 200
},
{
"user_id" : "1",
"branch_id" : "3",
"total" : 1400
},
{
"user_id" : "2",
"branch_id" : "1",
"total" : 100
},
{
"user_id" : "2",
"branch_id" : "1",
"total" : 100
},
I am looking to get output in the below format -
[
{
"user_id":"1",
"branch_id":"1",
"grand_total":"300"
},
{
"user_id":"1",
"branch_id":"3",
"grand_total":"1400"
},
{
"user_id":"2",
"branch_id":"1",
"grand_total":"200"
}
]
I have tried a mongo aggregate query, but the query gives output as undefined.
Basically I need to get per user wise per branch wise the total points he has earned.
Here is what I have tried but not working -
Collection.aggregate(
{
"$group": {
"_id": "$user_id",
"nameCount": { "$sum": 1 },
"branch_id": {
"$sum": {
"$cond": [ {"$branch_id":{"$ne":null}} ]
}
}
}
},
{
"$project": {
"_id": 0,
"name": "$_id",
"nameCount": 1,
"branch_id":1
}
}
);
Please help.
Your aggregation pipeline has to look like this:
{
"$group": {
"_id": {
user_id: "$user_id",
branch_id: "$branch_id"
},
"grand_total": {
"$sum": "$total"
},
}
}, {
"$project": {
"_id": 0,
"user_id": "$_id.user_id",
"branch_id": "$_id.branch_id",
"total": "$grand_total"
}
}
Inside your _id field in your "$group" pipeline you add the fields that you want to group your documents by. If you only want to group by one field you can write it as follows:
{"$group": {
"_id": "$user_id"
}
}
If you have multiple fields you want to group by (like it seems in your case) then you write it as follows:
{"$group": {
"_id": {
user_id: "$user_id",
branch_id: "$branch_id"
}
}
}
Every aggregation pipeline changes your document. So, in your $group if you call the sum of all totals like that "grand_total"
"grand_total": {
"$sum": "$total"
}
then in your $project pipeline that field total doesn't exist anymore. But instead we created a new field (grand_total) that is the sum.
{
"_id" : ObjectId("590b12b6330e1567acd29e69"),
"name": "Foo",
"sales_history" : [
{
"_id" : ObjectId("593ce8e4cfaa652df543d9e3"),
"sold_at" : ISODate("2017-06-11T06:53:24.881Z"),
"sold_to" : ObjectId("593509e938792e046ba14a02"),
"sold_products" : [
{
"product_dp" : 100,
"quantity" : 1,
"product_id" : ObjectId("591068be1f4c6c79a442a788"),
"_id" : ObjectId("593ce8e4cfaa652df543d9e5")
},
{
"product_dp" : 100,
"quantity" : 1,
"product_id" : ObjectId("593a33dccfaa652df543d924"),
"_id" : ObjectId("593ce8e4cfaa652df543d9e4")
}
]
},
{
"_id" : ObjectId("5944cb7142a04740357020b9"),
"sold_at" : ISODate("2017-06-17T06:25:53.332Z"),
"sold_to" : ObjectId("5927d4a59e58ba0c61066f3b"),
"sold_products" : [
{
"product_dp" : 500,
"quantity" : 1,
"price" : 5650,
"product_id" : ObjectId("593191ed53a2741dd9bffeb5"),
"_id" : ObjectId("5944cb7142a04740357020ba")
}
]
}
]
}
I have User schema like this. I want detail of product_id reference, with a date range search criteria on sold_at date field.
My expected data like following when I searched in sold_at at: 2017-06-11
{
"_id" : ObjectId("590b12b6330e1567acd29e69"),
"name": "Foo",
"sales_history" : [
{
"_id" : ObjectId("593ce8e4cfaa652df543d9e3"),
"sold_at" : ISODate("2017-06-11T06:53:24.881Z"),
"sold_to" : ObjectId("593509e938792e046ba14a02"),
"sold_products" : [
{
"product_dp" : 100,
"quantity" : 1,
"product_id": {
_id:ObjectId("hsfgg123412yh3gy1u2g3"),
name: "Product1",
code: "FG0154"
},
}
]
}
]
}
Product detail need to be populate in product_id, sales_history array need to be filtered in date range.
You can try below aggregation query.
$filter sales history on date range followed by $unwinding sales history & sold_products.
$lookup sold_products to get the product details.
$group back sold_products & sales history
db.collection.aggregate([
{
"$project": {
"name": 1,
"sales_history": {
"$filter": {
"input": "$sales_history",
"as": "history",
"cond": {
"$and": [
{
"$gte": [
"$$history.sold_at",
ISODate("2017-06-11T00:00:00.000Z")
]
},
{
"$lt": [
"$$history.sold_at",
ISODate("2017-06-12T00:00:00.000Z")
]
}
]
}
}
}
}
},
{
"$unwind": "$sales_history"
},
{
"$unwind": "$sales_history.sold_products"
},
{
"$lookup": {
"from": lookupcollection,
"localField": "sales_history.sold_products.product_id",
"foreignField": "_id",
"as": "sales_history.sold_products.product_id"
}
},
{
"$group": {
"_id": {
"_id": "$_id",
"sales_history_id": "$sales_history._id"
},
"name": {
"$first": "$name"
},
"sold_at": {
"$first": "$sales_history.sold_at"
},
"sold_to": {
"$first": "$sales_history.sold_to"
},
"sold_products": {
"$push": "$sales_history.sold_products"
}
}
},
{
"$group": {
"_id": "$_id._id",
"name": {
"$first": "$name"
},
"sales_history": {
"$push": {
"_id": "$_id.sales_history_id",
"sold_at": "$sold_at",
"sold_to": "$sold_to",
"sold_products": "$sold_products"
}
}
}
}
]);
I'm using MongoDB's aggregation pipeline, to get my documents in the form that I want. As the last step of aggregation, I use $project to put the documents into their final form.
But I'm having trouble projecting and array of sub-documents. Here is what I currently get from aggrgation:
{
"_id": "581c8c3df1325f68ffd23386",
"count": 14,
"authors": [
{
"author": {
"author": "57f246b9e01e6c6f08e1d99a",
"post": "581c8c3df1325f68ffd23386"
},
"count": 13
},
{
"author": {
"author": "5824382511f16d0f3fd5aaf2",
"post": "581c8c3df1325f68ffd23386"
},
"count": 1
}
]
}
I want to $project the authors array so that the return would be this:
{
"_id": "581c8c3df1325f68ffd23386",
"count": 14,
"authors": [
{
"_id": "57f246b9e01e6c6f08e1d99a",
"count": 13
},
{
"_id": "5824382511f16d0f3fd5aaf2",
"count": 1
}
]
}
How would I go about achieving that?
You can unwind the array and wind it u again after projecting.
Something like this:
db.collectionName.aggregate([
{$unwind:'$authors'},
{$project:{_id:1,count:1,'author.id':'$authors.author.author','author.count':'$authors.count'}},
{$group:{_id:{_id:'$_id',count:'$count'},author:{$push:{id:'$author.id',count:'$author.count'}}}},
{$project:{_id:0,_id:'$_id._id',count:'$_id.count',author:1}}
])
the output for above will be:
{
"_id" : "581c8c3df1325f68ffd23386",
"author" : [
{
"id" : "57f246b9e01e6c6f08e1d99a",
"count" : 13.0
},
{
"id" : "5824382511f16d0f3fd5aaf2",
"count" : 1.0
}
],
"count" : 14.0
}
I have been having the same problem and just now found a simple and elegant solution that has not been mentioned anywhere, so i thought I'd share it here:
You can iterate the array using $map and project each author. With the given structure, the aggregation should look somewhat like this
db.collectionName.aggregate([
$project: {
_id: 1,
count:1,
authors: {
$map: {
input: "$authors",
as: "author",
in: {
id: "$$author.author.author",
count: $$author.author.count
}
}
}
}
])
Hope this helps anyone who is looking, like me :)
Question:
"customFields" : [
{
"index" : "1",
"value" : "true",
"label" : "isOffline",
"dataType" : "check_box",
"placeholder" : "cf_isoffline",
"valueFormatted" : "true"
},
{
"index" : "2",
"value" : "false",
"label" : "tenure_extended",
"dataType" : "check_box",
"placeholder" : "cf_tenure_extended",
"valueFormatted" : "false"
}
],
Answer:
db.subscription.aggregate([
{$match:{"autoCollect" : false,"remainingBillingCycles" : -1,"customFields.value":"false", "customFields.label" : "isOffline"}},
{$project: {first: { $arrayElemAt: [ "$customFields", 1 ] }}}
])