I'm looking for the solution since yesterday, but can't find it. I tried different approaches like $elemMatch, aggregation etc. but nothing works. Either I get all objects or just the first one, but never only that ones with the matching IDs.
What I try to achieve: Get all objects of an array with one of multiple IDs.
First parameter is the user ID like 60a3f7d0f988f1e57212a81e. Every Document in this collection is unique by the user ID.
Second parameter is an array like ['609d1cfe0806daba1b0502bf', '609d1bba887035b9cd4292aa'] that consists of different IDs to be matched with the objects of the array words.
My approach gets only the first object and doesn't even work with an array of IDs (wordIDs) as parameter.
Words.prototype.getSpecificPersonalWords = async function(userID, wordIDs) {
const words = await personalWords.aggregate([
{$match:
{"user_id": userID}
},
{$unwind:
{"path": "$words"}
},
{$match:
{"words.word_id": { $in: ['609d1cfe0806daba1b0502bf', '609d1bba887035b9cd4292aa'] } }
}
])
return words
}
Document, that I want to query:
{
"_id": {
"$oid": "60a3f7d0f988f1e57212a81e"
},
"user_id": "609d22188ea8aebac56f9dc3",
"__v": {
"$numberInt": "0"
},
"words": [{
"word_id": "609d1bba887035b9cd4292aa",
"last_practiced": "2021-05-15 16:00:00",
"strength": {
"$numberInt": "1"
}
}, {
"word_id": "609d1c35861d99b9effc0027",
"last_practiced": "2021-05-15 16:00:00",
"strength": {
"$numberInt": "1"
}
}, {
"word_id": "609d1dcbc99e8dba538208d7",
"last_practiced": "2021-05-15 16:00:00",
"strength": {
"$numberInt": "1"
}
}]
}
Schema of that document
{
user_id: {
type: String,
unique: true
},
words: Array
});
I hope someone can help me to figure this out. Thanks in advance.
$match both user_id and word_id conditions
$filter to iterate loop of words and match condition id word_id in array of ids
const words = await personalWords.aggregate([
{
$match: {
"user_id": "609d22188ea8aebac56f9dc3",
"words.word_id": {
$in: ["609d1cfe0806daba1b0502bf", "609d1bba887035b9cd4292aa"]
}
}
},
{
$addFields: {
words: {
$filter: {
input: "$words",
cond: {
$in: [
"$$this.word_id",
["609d1cfe0806daba1b0502bf", "609d1bba887035b9cd4292aa"]
]
}
}
}
}
}
])
Playground
Related
I have the following mongo db schema and I am trying to build an aggregate query that searches under github_open_issues under the repo key and can return me a match for all the values with repoA as the value. I have tried the following as my query however its not returning any result. Im a bit confused why this is not working as I have another db with a schema similar to this and this type of query works there but here something seems to be different and is not working. I have also put together this interactive example mongoplayground
query
db.collection.aggregate([
{
"$unwind": "$github_open_issues"
},
{
"$match": {
"github_open_issues.repo": {
"$in": [
"repoA"
]
}
}
},
])
schema
[
{
"github_open_issues": {
"0": {
"git_url": "https://github.com/",
"git_assignees": "None",
"git_open_date": "2019-09-26",
"git_id": 253113,
"repo": "repoA",
"git_user": "userA",
"state": "open"
},
"1": {
"git_url": "https://github.com/",
"git_assignees": "None",
"git_open_date": "2019-11-15",
"git_id": 294398,
"repo": "repoB",
"git_user": "userB",
"state": "open"
},
"2": {
"git_url": "https://github.com/",
"git_assignees": "None",
"git_open_date": "2021-04-12",
"git_id": 661208,
"repo": "repoA",
"state": "open"
}
},
"unique_label_seen": {
"568": {
"label_name": "some label",
"times_seen": 12,
"535": {
"label_name": "another label",
"times_seen": 1
}
}
}
}
]
$objectToArray convert github_open_issues object to array in key-value format
$filter to iterate loop of above converted array and filter your search condition
$match to filter github_open_issues not empty
$arrayToObject convert github_open_issues array to object
db.collection.aggregate([
{
$addFields: {
github_open_issues: {
$filter: {
input: { $objectToArray: "$github_open_issues" },
cond: { $in: ["$$this.v.repo", ["repoA"]] }
}
}
}
},
{ $match: { github_open_issues: { $ne: [] } } },
{ $addFields: { github_open_issues: { $arrayToObject: "$github_open_issues" } } }
])
Playground
You query is correct but you data in schema placed wrong inside github_open_issues.repo your objects are place by numbers like {"0": {values... }, "1":{values... }} which cannot get your desired value. You can check the playground now playground
Is there any way to give order or rankings to MongoDB aggregation results?
My result is:
{
"score":100
"name": "John"
},
{
"score":80
"name": "Jane"
},
{
"score":60
"name": "Lee"
}
My wanted result is:
{
"score":100
"name": "John",
"rank": 1
},
{
"score":80
"name": "Jane"
"rank": 2
},
{
"score":60
"name": "Lee"
"rank": 3
}
I know there is a operator called $includeArrayIndex but this only works with $unwind operator.
Is there any way to give rank without using $unwind?
Using $unwind requires grouping on my collection, and I'm afraid grouping pipeline would be too huge to process.
The other way is to use $map and add rank in document using its index, and don't use $unwind stage because it would be single field array you can directly access using its key name as mention in last line of code,
$group by null and make array of documents in root array,
$map to iterate loop of root array, get the index of current object from root array using $indexOfArray and increment that returned index number using $add because index start from 0, and that is how we are creating rank field, merge object with current element object and rank field using $mergeObjects
let result = await db.collection.aggregate([
{
$group: {
_id: null,
root: {
$push: "$$ROOT"
}
}
},
{
$project: {
_id: 0,
root: {
$map: {
input: "$root",
in: {
$mergeObjects: [
"$$this",
{
rank: { $add: [{ $indexOfArray: ["$root", "$$this"] }, 1] }
}
]
}
}
}
}
}
]);
// you can access result using root key
let finalResult = result[0]['root'];
Playground
I have an Event document structured like so and I'm trying to query against the employeeResponses array to gather all responses (which may or may not exist) for a single employee:
[
{
...
eventDate: 2019-10-08T03:30:15.000+00:00,
employeeResponses: [
{
_id:"5d978d372f263f41cc624727",
response: "Available to work.",
notes: ""
},
...etc
];
}
];
My current mongoose aggregation is:
const eventResponses = await Event.aggregate([
{
// find all events for a selected month
$match: {
eventDate: {
$gte: startOfMonth,
$lte: endOfMonth,
},
},
},
{
// unwind the employeeResponses array
$unwind: {
path: "$employeeResponses",
preserveNullAndEmptyArrays: true,
},
},
{
$group: {
_id: null,
responses: {
$push: {
// if a response id matches the employee's id, then
// include their response; otherwise, it's a "No response."
$cond: [
{ $eq: ["$employeeResponses._id", existingMember._id] },
"$employeeResponses.response",
"No response.",
],
},
},
},
},
{ $project: { _id: 0, responses: 1 } },
]);
As you'll no doubt notice, the query above won't work after more than 1 employee records a response because it treats each individual response as a T/F condition, instead of all of the responses within the employeeResponses array as a single T/F condition.
As a result, I had remove all subsequent queries after the initial $match and do a manual reduce:
const responses = eventResponses.reduce((acc, { employeeResponses }) => {
const foundResponse = employeeResponses.find(response => response._id.equals(existingMember._id));
return [...acc, foundResponse ? foundResponse.response : "No response."];
}, []);
I was wondering if it's possible to achieve the same reduce result above, but perhaps using mongo's $reduce function? Or refactor the aggregation query above to treat all responses within the employeeResponses as a single T/F condition?
The ultimate goal of this aggregation is extract any previously recorded employee's responses and/or lack of a response from each found Event within a current month and place their responses into a single array:
["I want to work.", "Available to work.", "Not available to work.", "No response.", "No response." ...etc]
You can use $filter with $map to reshape your data and filter by _id. Then you can keep using $push with $ifNull to provide default value if an array is empty:
db.collection.aggregate([
{
$addFields: {
employeeResponses: {
$map: {
input: {
$filter: {
input: "$employeeResponses",
cond: {
$eq: [ "$$this._id", "5d978d372f263f41cc624727"]
}
}
},
in: "$$this.response"
}
}
}
},
{
$group: {
_id: null,
responses: { $push: { $ifNull: [ { $arrayElemAt: [ "$employeeResponses", 0 ] }, "No response" ] } }
}
}
])
Mongo Playground
I am attempting to do a mongodb regex query on a field. I'd like the query to prioritize a full match if it finds one and then partials afterwards.
For instance if I have a database full of the following entries.
{
"username": "patrick"
},
{
"username": "robert"
},
{
"username": "patrice"
},
{
"username": "pat"
},
{
"username": "patter"
},
{
"username": "john_patrick"
}
And I query for the username 'pat' I'd like to get back the results with the direct match first, followed by the partials. So the results would be ordered ['pat', 'patrick', 'patrice', 'patter', 'john_patrick'].
Is it possible to do this with a mongo query alone? If so could someone point me towards a resource detailing how to accomplish it?
Here is the query that I am attempting to use to perform this.
db.accounts.aggregate({ $match :
{
$or : [
{ "usernameLowercase" : "pat" },
{ "usernameLowercase" : { $regex : "pat" } }
]
} })
Given your precise example, this could be accomplished in the following way - if your real world scenario is a little bit more complex you may hit problems, though:
db.accounts.aggregate([{
$match: {
"username": /pat/i // find all documents that somehow match "pat" in a case-insensitive fashion
}
}, {
$addFields: {
"exact": {
$eq: [ "$username", "pat" ] // add a field that indicates if a document matches exactly
},
"startswith": {
$eq: [ { $substr: [ "$username", 0, 3 ] }, "pat" ] // add a field that indicates if a document matches at the start
}
}
}, {
$sort: {
"exact": -1, // sort by our primary temporary field
"startswith": -1 // sort by our seconday temporary
}
}, {
$project: {
"exact": 0, // get rid of the "exact" field,
"startswith": 0 // same for "startswith"
}
}])
Another way would be using $facet which may prove a bit more powerful by enabling more complex scenarios but slower (several people here will hate me, though, for this proposal):
db.accounts.aggregate([{
$facet: { // run two pipelines against all documents
"exact": [{ // this one will capture all exact matches
$match: {
"username": "pat"
}
}],
"others": [{ // this one will capture all others
$match: {
"username": { $ne: "pat", $regex: /pat/i }
}
}]
}
}, {
$project: {
"result": { // merge the two arrays
$concatArrays: [ "$exact", "$others" ]
}
}
}, {
$unwind: "$result" // flatten the resulting array into separate documents
}, {
$replaceRoot: { // restore the original document structure
"newRoot": "$result"
}
}])
I'm trying to return a specific collection, however, I want to filter an array within the collection. I'm not sure if this is possible. In the example below I'm trying to return the collection with _id: 7ARk3dc2JA8g5pamA and filter out the array object for "candidateUserId": "2". I'm doing this in a Meteorjs application.
Eg: `Collection'
{
"_id": "7ARk3dc2JA8g5pamA",
"jobTitle": "Developer",
"candidateApplication": [
{
"candidateUserId": "1",
"applied": true
},
{
"candidateUserId": "2",
"applied": false
}
]
}
Path: Publish command
return Jobs.find({ _id: 7ARk3dc2JA8g5pamA }, {
$filter: {
input: candidateApplication,
cond: { candidateUserId: { $eq: 1 } }
}
});
Jobs.find({ _id: 7ARk3dc2JA8g5pamA }, { candidateApplication: { $elemMatch: { candidateUserId: 2 } } }
This should return the document with only the _id and the candidateUserId array, but that array will now only contain the object that you want.
{ "_id" : 7ARk3dc2JA8g5pamA, "candidateApplication" : [ { "candidateUserId": 2, "applied": false } ] }
You can then get to the data with candidateApplication[0].candidateUserId and candidateApplication[0].applied
As mentioned in the comments above, if there are more instances of that same candidateUserId, only the first will be returned.