Basically the structure is :
{
"_id" : ObjectId("123123"),
"stores" : [
{
"messages" : [
{
"updated_time" : "2018-05-15T05:12:25+0000",
"message_count" : 4,
"thread_id" : "123",
"messages" : [
{
"message" : "Hi User ",
"created_time" : "2018-05-15T05:12:25+0000",
"message_id" : "111",
},
{
"message" : "This is tes",
"created_time" : "2018-05-15T05:12:21+0000",
"message_id" : "222",
}
]
},
],
"store_id" : "123"
}
]
}
I have these values to get message_id object : 111. So how to get this object, any idea or help will be appreciated. THanks
store_id: 123,
thread_id:123,
message_id:111
The simplest way would be to $unwind all the nested arrays and then use $match to get single document. You can also add $replaceRoot to get only nested document. Try:
db.collection.aggregate([
{ $unwind: "$stores" },
{ $unwind: "$stores.messages" },
{ $unwind: "$stores.messages.messages" },
{ $match: { "stores.store_id": "123", "stores.messages.thread_id": "123", "stores.messages.messages.message_id": "111" } },
{ $replaceRoot: { newRoot: "$stores.messages.messages" } }
])
Prints:
{
"created_time": "2018-05-15T05:12:25+0000",
"message": "Hi User ",
"message_id": "111"
}
To improve the performance you can use $match after every $unwind to filter out unnecessary data as soon as possible, try:
db.collection.aggregate([
{ $unwind: "$stores" },
{ $match: { "stores.store_id": "123" } },
{ $unwind: "$stores.messages" },
{ $match: { "stores.messages.thread_id": "123" } },
{ $unwind: "$stores.messages.messages" },
{ $match: { "stores.messages.messages.message_id": "111" } },
{ $replaceRoot: { newRoot: "$stores.messages.messages" } }
])
Related
Given the following document data in collection called 'blah'...
[
{
"_id" : ObjectId("60913f55987438922d5f0db6"),
"procedureCode" : "code1",
"description" : "Description 1",
"coding" : [
{
"system" : "ABC",
"code" : "L111"
},
{
"system" : "DEFG",
"code" : "S222"
}
]
},
{
"_id" : ObjectId("60913f55987438922d5f0dbc"),
"procedureCode" : "code2",
"description" : "Description 2",
"coding" : [
{
"system" : "ABC",
"code" : "L999"
},
{
"system" : "DEFG",
"code" : "X3333"
}
]
}
]
What I want to get is all of the coding elements where system is ABC for all parents, and an array of codes like so.
[
{ "code": "L111" },
{ "code": "L999" },
]
If I use db.getCollection('blah').find({"coding.system": "ABC"}) I get the parent document with any child in the coding array of ICD.
If I use...
db.getCollection("blah")
.find({ "coding.system": "ABC" })
.projection({ "coding.code": 1 })
I do get the parent documents which have a child with a system of "ABC", but the coding for "DEFG" seems to come along for the ride too.
{
"_id" : ObjectId("60913f55987438922d5f0db6"),
"coding" : [
{
"code" : "L989"
},
{
"code" : "S102"
}
]
},
{
"_id" : ObjectId("60913f55987438922d5f0dbc"),
"coding" : [
{
"code" : "L989"
},
{
"code" : "X382"
}
]
}
I have also tried experimenting with:
db.getCollection("blah").aggregate(
{ $unwind: "$coding" },
{ $match: { "system": "ICD" } }
);
.. as per this page: mongoDB query to find the document in nested array
... but go no where fast with that approach. i.e. no records at all.
What query do I need, please, to achieve something like this..?
[
{ "code": "L111" },
{ "code": "L999" },
...
]
or even better, this..?
[
"L111",
"L999",
...
]
db.collection.aggregate([
{
$match: { "coding.system": "ABC" }
},
{
$unwind: "$coding"
},
{
$match: { "coding.system": "ABC" }
},
{
$project: { code: "$coding.code" }
}
])
mongoplayground
db.collection.aggregate([
{
$match: { "coding.system": "ABC" }
},
{
$unwind: "$coding"
},
{
$match: { "coding.system": "ABC" }
},
{
$group: {
_id: null,
coding: { $push: "$coding.code" }
}
}
])
mongoplayground
Instead of $unwind, $match you can also use $filter:
db.collection.aggregate([
{ $match: { "coding.system": "ABC" } },
{
$project: {
coding: {
$filter: {
input: "$coding",
cond: { $eq: [ "$$this.system", "ABC" ] }
}
}
}
}
])
given below is my data in mongo db.I want to fetch all the unique ids from the field articles ,which is nested under the jnlc_subjects index .The result should contain only the articles array with distinct object Ids.
Mongo Data
{
"_id" : ObjectId("5c9216f1a21a4a31e0c7fa56"),
"jnlc_journal_category" : "Biology",
"jnlc_subjects" : [
{
"subject" : "Conservation Biology",
"views" : "123",
"articles" : [
ObjectId("5c4e93d0135edb6812200d5f"),
ObjectId("5c4e9365135edb6a12200d60"),
ObjectId("5c4e93a8135edb6912200d61")
]
},
{
"subject" : "Micro Biology",
"views" : "20",
"articles" : [
ObjectId("5c4e9365135edb6a12200d60"),
ObjectId("5c4e93d0135edb6812200d5f"),
ObjectId("5c76323fbaaccf5e0bae7600"),
ObjectId("5ca33ce19d677bf780fc4995")
]
},
{
"subject" : "Marine Biology",
"views" : "8",
"articles" : [
ObjectId("5c4e93d0135edb6812200d5f")
]
}
]
}
Required result
I want to get output in following format
articles : [
ObjectId("5c4e9365135edb6a12200d60"),
ObjectId("5c4e93a8135edb6912200d61"),
ObjectId("5c76323fbaaccf5e0bae7600"),
ObjectId("5ca33ce19d677bf780fc4995"),
ObjectId("5c4e93d0135edb6812200d5f")
]
Try as below:
db.collection.aggregate([
{
$unwind: "$jnlc_subjects"
},
{
$unwind: "$jnlc_subjects.articles"
},
{ $group: {_id: null, uniqueValues: { $addToSet: "$jnlc_subjects.articles"}} }
])
Result:
{
"_id" : null,
"uniqueValues" : [
ObjectId("5ca33ce19d677bf780fc4995"),
ObjectId("5c4e9365135edb6a12200d60"),
ObjectId("5c4e93a8135edb6912200d61"),
ObjectId("5c4e93d0135edb6812200d5f"),
ObjectId("5c76323fbaaccf5e0bae7600")
]
}
Try with this
db.collection.aggregate([
{
$unwind:{
path:"$jnlc_subjects",
preserveNullAndEmptyArrays:true
}
},
{
$unwind:{
path:"$jnlc_subjects.articles",
preserveNullAndEmptyArrays:true
}
},
{
$group:{
_id:"$_id",
articles:{
$addToSet:"$jnlc_subjects.articles"
}
}
}
])
If you don't want to $group with _id ypu can use null instead of $_id
According to description as mentioned into above question,as a solution to it please try executing following aggregate operation.
db.collection.aggregate(
// Pipeline
[
// Stage 1
{
$match: {
"_id": ObjectId("5c9216f1a21a4a31e0c7fa56")
}
},
// Stage 2
{
$unwind: {
path: "$jnlc_subjects",
}
},
// Stage 3
{
$unwind: {
path: "$jnlc_subjects.articles"
}
},
// Stage 4
{
$group: {
_id: null,
articles: {
$addToSet: '$jnlc_subjects.articles'
}
}
},
// Stage 5
{
$project: {
articles: 1,
_id: 0
}
},
]
);
I have this data structure:
"_id" : "121212",
"terms" : [
{
"term" : "hi",
"tf" : 2
},
{
"term" : "you",
"tf" : 1
}
]
}
and making this query:
db.foo.aggregate( [
{
$match : { _id : "121212" }
},
{
$project:{ terms:1 }
},
{
$unwind: "$terms"
}
]).pretty();
I have come to get this result in my db:
{
"_id" : "121212",
"terms" : {
"term" : "hi",
"tf" : 2
}
}
{
"_id" : "121212",
"terms" : {
"term" : "you",
"tf" : 1
}
}
but is there any way to get a result like this?:
{
"_id" : "121212",
"term" : "hi",
"tf" : 2
}
{
"_id" : "121212",
"term" : "you",
"tf" : 1
}
I have tried to build the query with $ replaceRoot: {newRoot: "$ terms"}, but after I can't select the _id field anymore.
Well, you can use the $map and $mergeObjects to do this beautifully.
[
{ "$match":{"_id":"121212"}},
{
"$addFields":{
"terms":{
"$map":{
"input":"$terms",
"in":{
"$mergeObjects":[
"$$this",
{
"_id":"$_id"
}
]
}
}
}
}
}
]
If you really need to deconstruct the "terms" array, then add the $unwind: "$terms" to the pipeline.
You can achieve by using $project stage at the end of the pipeline
db.foo.aggregate([
{ "$match" : { "_id": "121212" } },
{ "$unwind": "$terms" },
{ "$project": { "term": "$terms.term", "tf": "$terms.tf" }}
])
Output
[
{
"_id": "121212",
"term": "hi",
"tf": 2
},
{
"_id": "121212",
"term": "you",
"tf": 1
}
]
Check it here
You need to use $mergeObjects inside $replaceRoot:
db.foo.aggregate( [
{
$match : { _id : "121212" }
},
{
$project:{ terms:1 }
},
{
$unwind: "$terms"
},
{
$replaceRoot: {
newRoot: {
$mergeObjects: [ { _id: "$_id" }, "$terms" ]
}
}
}
]).pretty();
Just to complete the range of options:
db.foo.aggregate([
{ "$match" : { "_id": "121212" } }, // filter by "_id"
{ "$addFields": { "terms._id": "$_id" } }, // copy "_id" field into terms
{ "$unwind": "$terms" }, // flatten the "terms" array
{ "$replaceRoot": { "newRoot": "$terms" } } // move the contents of the "terms" field up to the root level
])
I am currently getting a response in mongoose like this
{
"_id" : "5a0be40836341c8ef9dc6d9d",
"Username" : "Adkins Daugherty",
"ContactDetail" : {
"ApiID" : "5a0be408ed6983954888bdb5",
"ContactName" : "Pace Roach",
}
}
But i want like this :
{
"_id" : "5a0be40836341c8ef9dc6d9d",
"Username" : "Adkins Daugherty",
"ApiID" : "5a0be408ed6983954888bdb5",
"ContactName" : "Pace Roach",
}
How can i do this using mongoose. My collection name is contacts
Thanks
EDIT-1
db.contacts.aggregate([{
$match: { Username: 'year_Adkins Daugherty' } },
{ "$unwind": "$ContactDetail" },
{
"$group": { "_id": "$_id",
"ApiID": "$ContactDetail.ApiID"
}
}
])
I think I got an answer in $project
return Contact.aggregate(
[
{ $match: { Username: regex } },
{
$project:{
Username:1,
ApiID:"$ContactDetail.ApiID",
Name:"$ContactDetail.ContactName",
ProfileImageUrl:"$ContactDetail.ProfileImageUrl",
OutletName:"$ContactDetail.OutletName"
}
}
]
).exec()
The result I got is
{
"_id": "5a0be40836341c8ef9dc6d9d",
"Username": "year_Adkins Daugherty",
"ApiID": "5a0be408ed6983954888bdb5",
"Name": "Pace Roach",
"ProfileImageUrl": "http://placehold.it/256x256",
"OutletName": "Codehow___kjvolyi3ye"
}
My documents look like this:
{
"_id": "1",
"tags": [
{ "code": "01-01", "type": "machine" },
{ "code": "04-06", "type": "gearbox" },
{ "code": "07-01", "type": "machine" }
]
},
{
"_id": "2",
"tags": [
{ "code": "03-04","type": "gearbox" },
{ "code": "01-01", "type": "machine" },
{ "code": "04-11", "type": "machine" }
]
}
I want to get distinct codes only for tags whose type is "machine". so, for the example above, the result should be ["01-01", "07-01", "04-11"].
How do I do this?
Using $unwind and then $group with the tag as the key will give you each tag in a separate document in your result set:
db.collection_name.aggregate([
{
$unwind: "$tags"
},
{
$match: {
"tags.type": "machine"
}
},
{
$group: {
_id: "$tags.code"
}
},
{
$project:{
_id:false
code: "$_id"
}
}
]);
Or, if you want them put into an array within a single document, you can use $push within a second $group stage:
db.collection_name.aggregate([
{
$unwind: "$tags"
},
{
$match: {
"tags.type": "machine"
}
},
{
$group: {
_id: "$tags.code"
}
},
{
$group:{
_id: null,
codes: {$push: "$_id"}
}
}
]);
Another user suggested including an initial stage of { $match: { "tags.type": "machine" } }. This is a good idea if your data is likely to contain a significant number of documents that do not include "machine" tags. That way you will eliminate unnecessary processing of those documents. Your pipeline would look like this:
db.collection_name.aggregate([
{
$match: {
"tags.type": "machine"
}
},
{
$unwind: "$tags"
},
{
$match: {
"tags.type": "machine"
}
},
{
$group: {
_id: "$tags.code"
}
},
{
$group:{
_id: null,
codes: {$push: "$_id"}
}
}
]);
> db.foo.aggregate( [
... { $unwind : "$tags" },
... { $match : { "tags.type" : "machine" } },
... { $group : { "_id" : "$tags.code" } },
... { $group : { _id : null , "codes" : {$push : "$_id"} }}
... ] )
{ "_id" : null, "codes" : [ "04-11", "07-01", "01-01" ] }
A better way would be to group directly on tags.type and use addToSet on tags.code.
Here's how we can achieve the same output in 3 stages of aggregation :
db.name.aggregate([
{$unwind:"$tags"},
{$match:{"tags.type":"machine"}},
{$group:{_id:"$tags.type","codes":{$addToSet:"$tags.code"}}}
])
Output : { "_id" : "machine", "codes" : [ "04-11", "07-01", "01-01" ] }
Also, if you wish to filter out tag.type codes, we just need to replace "machine" in match stage with desired tag.type.