my collection is like:
{
"_id" : ObjectId("5e2664ddd692"),
"distance" : "30F75Mg",
"UpStreamsValue" : "300mbpsx75mbps75mbps"
}
I need to add another distance column with value 30F75M, please update me how can i use below query:
db.streams.updateMany(
{
"_id" : ObjectId("5e2664ddd692"),
"distance" : "30F75Mg"
},
{
$set:{
"distance": "30F75M"
}
},
{
multi: true,
arrayFilters: [{"elem.attributeName": "hsiaDownUpStreamsValue", "elem.attributeValue": "300mbpsx75mbps"}]
}
);
You need to insert into the DB.
db.collection.insert({"distance" : "30F75M", "UpStreamsValue" : "300mbpsx75mbps" })
MongoDB will it self create an unique _id.
Related
I have been trying to update an Object for this collection. Below is the collection. Looking for Server 3.6 version.
Here The ask is Need to update the class name from "HISTORY" to " HISTORY_NEW". Need to do, for some students in the class. Need a query that will select all student records in student collection with "HISTORY" class in it and update them to "HISTORY_NEW ". I have around 30,000 records and not getting a bulk update method.
{
"_id" : ObjectId("611f90aa43f77a728879c395"),
"studentId" : "stu1",
"classes" : {
"History" : {
"TeacherName" : "T1",
"Marks" : [
{
"Internal": 15
}
]
},
"Geography" : {
"TeacherName" : "T2",
"Marks" : [
{
"Internal" : 20
}
]
}
},
"updateDate" : ISODate("2021-10-12T11:40:47.156Z")
}
This is the result I am expecting
{
"_id" : ObjectId("611f90aa43f77a728879c395"),
"studentId" : "stu1",
"classes" : {
"HISTORY_NEW" : {
"TeacherName" : "T1",
"Marks" : [
{
"Internal": 15
}
]
},
"Geography" : {
"TeacherName" : "T2",
"Marks" : [
{
"Internal" : 20
}
]
}
},
"updateDate" : ISODate("2021-10-12T11:40:47.156Z")
}
.Or is that even possible with the kind of collection above or going via code route?
So far this is what I have, without any success.
Get all students' Ids and then update the Class name. But that is also not working and don't think it is smart to update DB 30,000 times.
var studentIds =[];
db.studentSubject.find({"classes.History":{$exists:true}})
.forEach(function(u) { studentIds.push(u.studentId) })
studentIds.forEach(function(studentId) {
var result;
try {
result =db.studentSubject.updateOne(
{studentId:studentId},
{ $set : {"classes.History": "HISTORY_NEW",}},
{ upsert: false});
} catch (e) {
print(e);
}
});
From your scenario, you need $rename operator.
As discussed in the comment, you don't need to fetch each document to get studentId and then pass it to update each document. Just bulk update by checking the document has classes.History field.
db.collection.update({
"classes.History": {
$exists: true
}
},
{
$rename: {
"classes.History": "classes.HISTORY_NEW"
}
},
{
upsert: false,
multi: true
})
Sample Mongo Playground
I have a Meteor Mongo document as shown below
{
"_id" : "zFndWBZTvZPgSKXHP",
"activityId" : "aRDABihAYFoAW7jbC",
"activityTitle" : "Test Mongo Document",
"users" : [
{
"id" : "b1#gmail.com",
"type" : "free"
},
{
"id" : "JqKvymryNaCjjKrAR",
"type" : "free"
},
],
}
I want to update a specific array element's email with custom generated id using Meteor query something like the below.
for instance, I want to update the document
if 'users.id' == "b1#gmail.com" then update it to users.id = 'SomeIDXXX'
So updated document should looks like below.
{
"_id" : "zFndWBZTvZPgSKXHP",
"activityId" : "aRDABihAYFoAW7jbC",
"activityTitle" : "Test Mongo Document",
"users" : [
{
"id" : "SomeIDXXX",
"type" : "free"
},
{
"id" : "JqKvymryNaCjjKrAR",
"type" : "free"
},
],
}
I have tried the below but didnt work.
Divisions.update(
{ activityId: activityId, "users.id": emailId },
{ $set: { "users": { id: _id } } }
);
Can someone help me with the relevant Meteor query ? Thanks !
Your query is actually almost right except for a small part where we want to identify the element to be updated by its index.
Divisions.update({
"activityId": "aRDABihAYFoAW7jbC",
"users.id": "b1#gmail.com"
}, {
$set: {"users.$.id": "b2#gmail.com"}
})
You might need the arrayFilters option.
Divisions.update(
{ activityId: activityId },
{ $set: { "users.$[elem].id": "SomeIDXXX" } },
{ arrayFilters: [ { "elem.id": "b1#gmail.com" } ], multi: true }
);
https://docs.mongodb.com/manual/reference/operator/update/positional-filtered/
You need to use the $push operator instead of $set.
{ $push: { <field1>: <value1>, ... } }
I have following model:
{
"_id" : ObjectId("5d61aaf8108e185191552bbb"),
"serials" : [
"e127av48-0697-4977-b096-5ce79c89a414",
"d163f80a-55ff-40fe-90b4-331ece5bebd5",
"4740021f-e9b5-4ca5-bf0e-8554c123bb94",
"320ffd42-f101-4b1d-8ff4-80bc693a29e6",
"fef5e68b-aed0-4a96-9488-7941c41d1c1f",
"2c0752ba-bf7a-4a3b-bd9f-14db4b2f8bae",
"6c5ff44d-5979-4bff-af12-9e6d282c3789",
"9c91bf91-72d7-4b71-827b-924947d6e93d",
"fb34b28e-afb1-4b6a-a3c1-5a1fe44246ee",
"91ab22ef-702f-4cbd-8919-a67a2b9a684c",
"ee1a7cb2-e088-47e6-a824-c8697df7d94c",
"0dc4c687-4db2-481e-a1a6-491320dede11",
"34612148-3e01-44ee-b262-de2035e63691",
"5ba85baf-e48a-40af-8578-55ff1a873c76",
"19fe3672-b6cb-4bb6-8d21-93412b938584",
"1d0d6f6d-1b49-461b-8661-ecbf43a6595e",
"d9a5455c-65ee-45e1-ae49-33cc15dec841",
"4a690a00-a76c-4d3e-aee3-78b2bb731b0c",
"ae331830-40b4-457c-8cc4-5d548f769c3e",
"fe3e460b-c89d-4ace-8a36-5ba2b53bf4d0",
"2cc6a2a0-e029-475f-a7fc-a46a79afb605",
"a7d07767-eada-4ce3-b083-9b048e9ae9f4"
],
"name" : "ApiCard",
"producer" : "Farmina",
"form" : "syrop",
"__v" : 0
}
I would like to retrive documents (multiple) from collection based on this serial numbers ("serials" field). For example i am finding:
[
"e127av48-0697-4977-b096-5ce79c89a414",
"d163f80a-55ff-40fe-90b4-331ece5bebd5",
"4740021f-e9b5-4ca5-bf0e-8554c123bb94",
"key that doesn't exist",
]
We have to assume that one of the serial number doesn't exist, so would like to get information for individual serial, expected output:
[
{
"serial":"e127av48-0697-4977-b096-5ce79c89a414",
"doc":{
....whole document where above serial is in array field "serials"
}
},
{
"serial":"e127av48-0697-4977-b096-5ce79c89a414",
"doc":{
....whole document where above serial is in array field "serials"
}
},
{
"serial":"e127av48-0697-4977-b096-5ce79c89a414",
"doc":{
....whole document where above serial is in array field "serials"
}
},
{
"serial":"key that doesn't exist",
"doc": null
}
]
I was trying the simplest solution - mongodb find by multiple array items, but unfortunately it'doesn't return info for individual serial number. I'am not sure it's possible to prepare this kind of query. I think some complex aggregation could perform it, but i don't even know this kind of pipelines.
Of course, i can get simple solution by using multiple aggregate or even find, but it could impact on performance, when application will be looking for 10000 records per request.
The following query can do the trick:
db.collection.aggregate([
{
$limit:1
},
{
$project:{
"_id":0,
"serialsToSearch":[
"e127av48-0697-4977-b096-5ce79c89a414",
"d163f80a-55ff-40fe-90b4-331ece5bebd5",
"4740021f-e9b5-4ca5-bf0e-8554c123bb94",
"key that doesn't exist",
]
}
},
{
$unwind:"$serialsToSearch"
},
{
$lookup:{
"from":"collection",
"let":{
"serial":"$serialsToSearch"
},
"pipeline":[
{
$match:{
$expr:{
$in:["$$serial","$serials"]
}
}
},
{
$project:{
"serials":0
}
}
],
"as":"searialsLookup"
}
},
{
$unwind:{
"path":"$searialsLookup",
"preserveNullAndEmptyArrays":true
}
},
{
$project:{
"serial":"$serialsToSearch",
"doc":{
$ifNull:["$searialsLookup",null]
}
}
}
]).pretty()
Data Set:
{
"_id" : ObjectId("5d61aaf8108e185191552bbb"),
"serials" : [
"e127av48-0697-4977-b096-5ce79c89a414",
"d163f80a-55ff-40fe-90b4-331ece5bebd5",
"4740021f-e9b5-4ca5-bf0e-8554c123bb94",
"320ffd42-f101-4b1d-8ff4-80bc693a29e6",
"fef5e68b-aed0-4a96-9488-7941c41d1c1f",
"2c0752ba-bf7a-4a3b-bd9f-14db4b2f8bae",
"6c5ff44d-5979-4bff-af12-9e6d282c3789",
"9c91bf91-72d7-4b71-827b-924947d6e93d",
"fb34b28e-afb1-4b6a-a3c1-5a1fe44246ee",
"91ab22ef-702f-4cbd-8919-a67a2b9a684c",
"ee1a7cb2-e088-47e6-a824-c8697df7d94c",
"0dc4c687-4db2-481e-a1a6-491320dede11",
"34612148-3e01-44ee-b262-de2035e63691",
"5ba85baf-e48a-40af-8578-55ff1a873c76",
"19fe3672-b6cb-4bb6-8d21-93412b938584",
"1d0d6f6d-1b49-461b-8661-ecbf43a6595e",
"d9a5455c-65ee-45e1-ae49-33cc15dec841",
"4a690a00-a76c-4d3e-aee3-78b2bb731b0c",
"ae331830-40b4-457c-8cc4-5d548f769c3e",
"fe3e460b-c89d-4ace-8a36-5ba2b53bf4d0",
"2cc6a2a0-e029-475f-a7fc-a46a79afb605",
"a7d07767-eada-4ce3-b083-9b048e9ae9f4"
],
"name" : "ApiCard",
"producer" : "Farmina",
"form" : "syrop",
"__v" : 0
}
Output:
{
"serial" : "e127av48-0697-4977-b096-5ce79c89a414",
"doc" : {
"_id" : ObjectId("5d61aaf8108e185191552bbb"),
"name" : "ApiCard",
"producer" : "Farmina",
"form" : "syrop",
"__v" : 0
}
}
{
"serial" : "d163f80a-55ff-40fe-90b4-331ece5bebd5",
"doc" : {
"_id" : ObjectId("5d61aaf8108e185191552bbb"),
"name" : "ApiCard",
"producer" : "Farmina",
"form" : "syrop",
"__v" : 0
}
}
{
"serial" : "4740021f-e9b5-4ca5-bf0e-8554c123bb94",
"doc" : {
"_id" : ObjectId("5d61aaf8108e185191552bbb"),
"name" : "ApiCard",
"producer" : "Farmina",
"form" : "syrop",
"__v" : 0
}
}
{ "serial" : "key that doesn't exist", "doc" : null }
Note: The query won't give expected output if the collection would be empty.
Aggregation stages details:
STAGE I: Limiting the records to 1, as initially, our motive is to inject the input array in aggregation. The injection would be done in no time.
STAGE II: Projecting the input array as serialsToSearch
STAGE III: Now we have the input array as a field, we can unwind it
STAGE IV: Lookup in the same collection with each field of the input array and check if the searched serial is present in serials array
STAGE V: unwinding the lookup output
STAGE VI: Projecting fields as per the response required.
It's one of my data as JSON format:
{
"_id" : ObjectId("5bfdb412a80939b6ed682090"),
"accounts" : [
{
"_id" : ObjectId("5bf106eee639bd0df4bd8e05"),
"accountType" : "DDA",
"productName" : "DDA1"
},
{
"_id" : ObjectId("5bf106eee639bd0df4bd8df8"),
"accountType" : "VSA",
"productName" : "VSA1"
},
{
"_id" : ObjectId("5bf106eee639bd0df4bd8df9"),
"accountType" : "VSA",
"productName" : "VSA2"
}
]
}
I want to make a query to get all productName(no duplicate) of accountType = VSA.
I write a mongo query:
db.Collection.distinct("accounts.productName", {"accounts.accountType": "VSA" })
I expect: ['VSA1', 'VSA2']
I get: ['DDA','VSA1', 'VSA2']
Anybody knows why the query doesn't work in distinct?
Second parameter of distinct method represents:
A query that specifies the documents from which to retrieve the distinct values.
But the thing is that you showed only one document with nested array of elements so whole document will be returned for your condition "accounts.accountType": "VSA".
To fix that you have to use Aggregation Framework and $unwind nested array before you apply the filtering and then you can use $group with $addToSet to get unique values. Try:
db.col.aggregate([
{
$unwind: "$accounts"
},
{
$match: {
"accounts.accountType": "VSA"
}
},
{
$group: {
_id: null,
uniqueProductNames: { $addToSet: "$accounts.productName" }
}
}
])
which prints:
{ "_id" : null, "uniqueProductNames" : [ "VSA2", "VSA1" ] }
There are 200 documents in school db. I must remove each document which has "type":"homework" and the lowest score.
{
"_id" : 0,
"name" : "aimee Zank",
"scores" :
[
{
"type" : "exam",
"score" : 1.463179736705023
},
{
"type" : "quiz",
"score" : 11.78273309957772
},
{
"type" : "homework",
"score" : 6.676176060654615
},
{
"type" : "homework",
"score" : 35.8740349954354
}
]
}
For example,here
{
"type" : "homework",
"score" : 6.676176060654615
}
must be removed as score = 6.6 < 35.8
I sorted all the documents like this:
db.students.find({"scores.type":"homework"}).sort({"scores.score":1})
But I do not know how then to remove the doc having the lowest score and type:homework???
NOTE: how to solve it by not using aggregation method? E.g., by sorting and then updating.
This can be done in a couple of steps. The first step is to grab a list of the documents with the minimum score by using the aggregation framework with $match, $unwind and $group operators that streamlines your documents to find the minimum score for each document:
lowest_scores_docs = db.school.aggregate([
{ "$match": {"scores.type": "homework"} },
{ "$unwind": "$scores" }, { "$match": {"scores.type": "homework"} },
{ "$group": { "_id":"$_id", "lowest_score": {"$min": "$scores.score" } } } ] )
The second step is to loop through the dictionary above and use the $pull operator in the update query to remove the element from the array as follows:
for result in lowest_scores_docs["result"]:
db.school.update({ "_id": result["_id"] },
{ "$pull": { "scores": { "score": result["lowest_score"] } } } )
import pymongo
import sys
# connnecto to the db on standard port
connection = pymongo.MongoClient("mongodb://localhost")
db = connection.school # attach to db
students = db.students # specify the colllection
try:
cursor = students.find({})
print(type(cursor))
for doc in cursor:
hw_scores = []
for item in doc["scores"]:
if item["type"] == "homework":
hw_scores.append(item["score"])
hw_scores.sort()
hw_min = hw_scores[0]
#students.update({"_id": doc["_id"]},
# {"$pull":{"scores":{"score":hw_min}}})
except:
print ("Error trying to read collection:" + sys.exc_info()[0])