MongoDB: retrieve only certain properties of a document after matching - database

I have a MongoDB collection called books.
An example of a document is:
{
"_id" : ObjectId("62bf10951fecaed4dba275b1"),
"name" : "Library 1",
"positions" : [
{
"number" : 2,
"nodes" : [
{
"number" : 2,
"bookId" : "6254674d3711f90bd8e76036"
},
{
"number" : 1,
"bookId" : "621e9b5aa7951d0be4516c18"
}
]
},
{
"number" : 1,
"nodes" : [
{
"number" : 1,
"bookId" : "6254674d3711f90bd8e76037"
},
{
"number" : 3,
"bookId" : "6254674d3711f90bd8e76039"
},
{
"number" : 2,
"bookId" : "6254674d3711f90bd8e76035"
}
]
}
]
}
I need to run a query that, based on a book ID, returns the name, the positions.number and the positions.node.number.
For example, if I search for the ID 6254674d3711f90bd8e76035, it should return:
{
_id: ObjectId("62bf10951fecaed4dba275b1"),
name: "Library 1",
positions: {
number: 1,
nodes: {
number: 2
}
}
}
So far, this is what I came out with:
db.getCollection('books').aggregate([
{ $match: { "positions.nodes.bookId": "6254674d3711f90bd8e76035" } },
{ $project: { name: 1, "positions.number": 1, "positions.nodes.number": 1 } }
])
Unfortunately, this returns every single node. I might need something that says:
"Select name, position.number, position.nodes.number where bookId = 6254674d3711f90bd8e76035"
Any help is appreciated.
Thanks

Solved:
db.getCollection('books').aggregate([
{
$match: {"positions.nodes.books": "6254674d3711f90bd8e76035"}
},
{
$unwind: "$positions"
},
{
$unwind: "$positions.nodes"
},
{
$match: {"positions.nodes.books": "6254674d3711f90bd8e76035"}
},
])

Related

How to projection element in multi array field of MongoDb collection?

Is there a way to get only specific field values ​​from a multi array?
db.test.insert({'id':'stack', 'nums':[{'name':'Dave', 'num': 1, 'phones' :[{'id':1, 'number':'000-000'}, {'id':2, 'number':'000-001'}]}]})
{
"_id" : "63b3896a5b5d9de96b6277fa",
"id" : "stack",
"nums" : [
{
"name" : "Dave",
"num" : 1,
"phones" : [
{
"id" : 1,
"number" : 0
},
{
"id" : 2,
"number" : -1
}
]
}
]
}
the answer i want
{'id':1, 'number':'000-000'}
I want to print only the value with 'id' 1 in 'phones'.
db.collection.aggregate([
{
"$unwind": "$nums"
},
{
$project: {
"phones": {
$filter: {
input: "$nums.phones",
cond: {$eq: ["$$this.id",1]
}
}
}
}
}
])
Playground

MongoDB: extra object created when updating with $addToSet

I'm encountering a strange behavior in MongoDB.
This is the schema of the documents in my collection:
{
"_id" : ObjectId("62bf10951fecaed4dba275b1"),
"name" : "Rack 1",
"type" : "rack",
"positions" : [
{
"number" : 1
},
{
"number" : 2
},
{
"number" : 3,
"nodes" : [
{
"number" : 1
}
]
},
{
"number" : 4,
"nodes" : [
{
"number" : 1
},
{
"number" : 2
},
{
"number" : 3
}
]
},
]
}
I would like to run two queries:
create a new position, if it doesn't exist yet
create a new object in the nodes array
I have created two queries so far:
db.getCollection('locations').updateOne(
{ _id: ObjectId("62bf10951fecaed4dba275b1") },
{ $addToSet: { 'positions': { number: 5 } } }
)
db.getCollection('locations').updateOne(
{ _id: ObjectId("62bf10951fecaed4dba275b1"), 'positions.number': 5 },
{ $addToSet: { 'positions.$.nodes': { number: 1 } } }
)
The second query creates a new element in nodes. BUT it also creates a new element in the positions array.
This is the erroneous object:
{
"_id" : ObjectId("62bf10951fecaed4dba275b1"),
"name" : "Rack 1",
"type" : "rack",
"positions" : [
{
"number" : 1
},
{
"number" : 2
},
{
"number" : 3,
"nodes" : [
{
"number" : 1
}
]
},
{
"number" : 4,
"nodes" : [
{
"number" : 1
},
{
"number" : 2
},
{
"number" : 3
}
]
},
{
"number" : 5,
"nodes" : [
{
"number" : 1
}
]
},
{
"number" : 5 <<<<<< THIS IS WRONG
},
]
}
Is there something I need to know or is simply the wrong query?
Many thanks
The two queries may run at different lengths of time and should not be executed synchronously.
Please try using some async/await style ordering to ensure that the second query does indeed execute when the first query is finished.
e.g. in javascript:
const myFunction = async () => {
await db.getCollection('locations').updateOne(
{ _id: ObjectId("62bf10951fecaed4dba275b1") },
{ $addToSet: { 'positions': { number: 5 } } }
)
await db.getCollection('locations').updateOne(
{ _id: ObjectId("62bf10951fecaed4dba275b1"), 'positions.number': 5 },
{ $addToSet: { 'positions.$.nodes': { number: 1 } } }
)
}
myFunction()

MongoDB nested filters application

I have data in mongodb with multiple fields, I am trying to filter data on basis of a field named create_date and then trying to fetch totalrecordscount along with further filtering the data. Following is the data structure:
"_id" : ObjectId("62a886a76034628f8028e8dc"),
"create_time" : "18:53:01",
"close_date" : "2022-05-09",
"close_time" : "13:34:43",
"country_code" : "US",
"closed_case" : 1,
"resolution_days" : 8,
"status_code" : "5",
"state_code" : "1",
"issue_resolved_flag" : "Yes",
"incident_created_by" : "09D4A6BB-C51E-EB11-A813-000D3A58F938",
"incident_modified_by" : "A3CBC776-DF3C-E711-810B-E0071B7284D1",
"modifiedon" : "2022-05-09 13:34:46.0",
"row_insertion_dttm" : "2022-06-14 02:58:21.202",
"data_source_category" : "CASE",
"resolution_duration_minutes" : 5060,
"create_date" : "2022-05-01",
"repeat_case_different_issue7_day" : 0,
"repeat_case_same_issue_7day" : 0,
"scr_7day" : 1,
"ocr_7day" : 0,
"csat_status" : "no"
I am able to aggregate the data on basis of create date and fetch the totalrecordscount for a particular date using following command :
country_code:1
}},
{
$match:{create_date:{$gt:"2022-06-01"}}
},
{$group:{ _id: {datebasis: "$create_date"},
TotalRecordscount: { $sum: 1 },
}
},
])
The output is: {
"_id" : {
"datebasis" : "2022-06-17"
},
"TotalRecordscount" : 13254.0
}
/* 2 */
{
"_id" : {
"datebasis" : "2022-06-14"
},
"TotalRecordscount" : 16688.0
}
/* 3 */
{
"_id" : {
"datebasis" : "2022-06-09"
},
"TotalRecordscount" : 15478.0
}
But my ask is to further group the data to get the number of records on a particular date for fields like "scr_7day" equals to 0 or "resolution_duration_minutes" < 1440.
Can you help me in achieving this?
Assume you solve the date string logic as mentioned in the comment, my answer just focuses on your question.
You can work with $count and $cond operators to calculate the documents by condition.
db.collection.aggregate([
{
$group: {
_id: {
datebasis: "$create_date"
},
TotalRecordscount: {
$sum: 1
},
scr_7dayIsZero: {
$sum: {
$cond: {
if: {
$eq: [
"$scr_7day",
0
]
},
then: 1,
else: 0
}
}
},
resolution_duration_minutesLessThan1440: {
$sum: {
$cond: {
if: {
$lt: [
"$resolution_duration_minutes",
1440
]
},
then: 1,
else: 0
}
}
}
}
}
])
Sample Mongo Playground

Need help in querying mongodb

I have a a few documents that have the following structure. See attached image.
document structure
Each document includes an array of 'FileMeta' objects and each FileMeta object includes an array of 'StatusHistory' objects. I'm trying to get only the FileMetas that contain StatusCode equal to 4 and that the TimeStamp is greater than a certain datetime.
Tried the following query but it only returns the first FileMeta element of each document.
db.getCollection('Collection').find({'ExternalParams.RequestingApplication':'aaa.bbb'},
{ "FileMeta": { $elemMatch: { "StatusHistory":{ $elemMatch:{ "StatusCode": 4, "TimeStamp": { $gt: ISODate("2020-06-28T11:02:26.542Z")} } } } }} )
What am I doing wrong?
here is the document structure:
{
"_id" : ObjectId("5ef84e2ec08abf38b0043ab4"),
"FileMeta" : [
{
"StatusHistory" : [
{
"StatusCode" : 0,
"StatusDesc" : "New File",
"TimeStamp" : ISODate("2020-06-28T11:00:46.286Z")
},
{
"StatusCode" : 2,
"StatusDesc" : "stby",
"TimeStamp" : ISODate("2020-06-28T11:02:20.400Z")
},
{
"StatusCode" : 4,
"StatusDesc" : "success",
"TimeStamp" : ISODate("2020-06-28T11:02:26.937Z")
}
]
},
{
"StatusHistory" : [
{
"StatusCode" : 0,
"StatusDesc" : "New File",
"TimeStamp" : ISODate("2020-06-28T11:00:46.286Z")
},
{
"StatusCode" : 2,
"StatusDesc" : "stby",
"TimeStamp" : ISODate("2020-06-28T11:02:20.617Z")
},
{
"StatusCode" : 4,
"StatusDesc" : "success",
"TimeStamp" : ISODate("2020-06-28T11:02:26.542Z")
}
]
}
],
}
I want to return only the FileMeta objects that include a StatusHistory that match the following conditions: StatusCode = 4 and TimeStamp > SomeDateTime
Sorry for the delay, mate, I've been quite busy lately. Hope you already solved your problem. Anyway, I think that I found the solution.
As you can see on this link, the example shows that by default the $elemMatch operator returns the whole array in case of match on any element.
For instance, consider the following collection:
{ _id: 1, results: [ { product: "abc", score: 10 }, { product: "xyz", score: 5 } ] }
{ _id: 2, results: [ { product: "abc", score: 8 }, { product: "xyz", score: 7 } ] }
{ _id: 3, results: [ { product: "abc", score: 7 }, { product: "xyz", score: 8 } ] }
If you do the following query, for example:
db.survey.find(
{ results: { $elemMatch: { product: "xyz", score: { $gte: 8 } } } }
)
The output will be:
{ "_id" : 3, "results" : [ { "product" : "abc", "score" : 7 }, { "product" : "xyz", "score" : 8 } ] }
Not:
{ "_id" : 3, "results" : [{ "product" : "xyz", "score" : 8 }]}
That said, if you want to return only the document in the array that matches the specified query, you must use the db.collection.aggregate() function with the $unwind and $match operator.
The query below shall give you what you want.
Query:
db.collection.aggregate([
{"$unwind" : "$FileMeta"},
{"$unwind" : "$FileMeta.StatusHistory"},
{
"$match" : {
"FileMeta.StatusHistory.StatusCode" : 4,
"FileMeta.StatusHistory.TimeStamp" : {"$gte" : ISODate("2020-06-28T11:02:26.937Z")}
}
}
]).pretty()
Result:
{
"_id" : ObjectId("5ef84e2ec08abf38b0043ab4"),
"FileMeta" : {
"StatusHistory" : {
"StatusCode" : 4,
"StatusDesc" : "success",
"TimeStamp" : ISODate("2020-06-28T11:02:26.937Z")
}
}
}
One last tip. Consider changing your modeling to something that looks like the unwinded document, and remember that one document should be equivalent to one row in a normal relational database. So avoid storing information that should be on "several rows" on a single document.
Useful links:
The $elemMatch operator.
The $unwind operator.

Find specific field in an array of embedded documents

I'm trying to find specific element of array in my MongoDB document, but with all my tries query returns all array. How can I get the right object?
My collection's document looks like:
{
"Achievements": [
{
"AchievementID": 1,
"AchievementEventID": 0
},
{
"AchievementID": 2,
"AchievementEventID": 1
}
],
"Buildings": [
{
"BuildingID": 1,
"BuildingType": "type1"
},
{
"BuildingID": 2,
"BuildingType": "type1"
},
]
}
I tried to get only one element of my Achievements array:
db.data.find({'Achievements.AchievementEventID': 0})
I expected to get only element with AchievementEventID equal to 0:
{
"AchievementID": 1,
"AchievementEventID": 0
}
But I got whole Achievements array.
How I could get only specific element?
You can use the Aggregation query like in the following example. The sample achive collection has 3 documents:
{
"_id" : 1,
"Achievements" : [
{
"AchievementID" : 1,
"AchievementEventID" : 0
},
{
"AchievementID" : 2,
"AchievementEventID" : 1
}
],
"Buildings" : [
{
"BuildingID" : 1,
"BuildingType" : "type1"
},
{
"BuildingID" : 2,
"BuildingType" : "type1"
}
]
}
{
"_id" : 2,
"Achievements" : [
{
"AchievementID" : 2,
"AchievementEventID" : 2
}
],
"Buildings" : [
{
"BuildingID" : 2,
"BuildingType" : "type2"
}
]
}
{
"_id" : 3,
"Achievements" : [
{
"AchievementID" : 31,
"AchievementEventID" : 1
}
],
"Buildings" : [
{
"BuildingID" : 3,
"BuildingType" : "type3"
}
]
}
The Query:
db.achive.aggregate( [
{ $project: { Buildings: 0} },
{ $unwind: "$Achievements" },
{ $match: { "Achievements.AchievementEventID": { $eq: 1 } } }
])
=>
{ "_id" : 1, "Achievements" : { "AchievementID" : 2, "AchievementEventID" : 1 } }
{ "_id" : 3, "Achievements" : { "AchievementID" : 31, "AchievementEventID" : 1 } }
I added the _id field to identify the documents selected.
Updated Query:
db.achive.aggregate( [
{ $unwind: "$Achievements" },
{ $match: { "Achievements.AchievementEventID": { $eq: 1 } } },
{ $project: { AchievementID: "$Achievements.AchievementID", _id: 0} },
])
=>
{ "AchievementID" : 2 }
{ "AchievementID" : 31 }
You can use $elemMatch for that
db.data.find(
{ 'Achievements.AchievementEventID': 0},{Buildings:0, Achievements: {$elemMatch: {AchievementEventID: 0}}}
)
If the above solution doesn't for you then try the below one:
db.data.find({"Achievements.AchievementEventID": 0}, {Buildings: 0, 'Achievements.$': 1});
You can use aggregate instead of a find like this
db.data.aggregate(
[{'$unwind':'$Achievements'},{$match:{
'Achievements.AchievementEventID':0
}},{$project:{
'AchievementID':'$Achievements.AchievementID',
'AchievementEventID':'$Achievements.AchievementEventID'
}}]
);

Resources