I'm having two objects,
const originTimeStamp = {
chats: '2021-06-25T12:21:21.835+00:00',
users: '2021-06-21T12:21:21.835+00:00',
history: '2021-06-18T12:21:21.835+00:00'
}
const controlIds = {
chats: ['1bfe','2bfs','3bhr'],
users: ['6jkj'],
history: ['8her'],
}
and a collection that typically have some logs related to user activities:
{
controlId: '2bfs'
createdAt: '2021-07-19T12:21:21.835+00:00'
},
{
controlId: '6jkj'
createdAt: '2021-06-18T12:21:21.835+00:00'
},
{
controlId: '8her'
createdAt: '2021-06-25T12:21:21.835+00:00'
},
What I basically want to do is to filter out the controlIds object in such a way that if the control id exists in the collection and If the origin time stamp of that section say for chats '2021-06-25T12:21:21.835+00:00' < '2021-07-19T12:21:21.835+00:00' (of id '2bfs' from collection ) we will remove that id from the object.
Expected Result:
const controlIds = {
chats: ['1bfe','3bhr'],
users: ['6jkj'],
history: [],
}
Is there any way to achieve it with aggregation pipeline, right now i tried creating a flow but not able to do that? Here is the suggested flow i tried so far:
$match the documents with a particular range of timestamps
$project only the control_Id
$group them using $push to get all documents in an array
Assign this output to a variable and filter your object.
Related
I've recently started using MongoDB using Mongoose (from NodeJS), but now I got stuck updating a subdocument in an array.
Let me show you...
I've set up my Restaurant in MongoDB like so:
_id: ObjectId("5edaaed8d8609c2c47fd6582")
name: "Some name"
tables: Array
0: Object
id: ObjectId("5ee277bab0df345e54614b60")
status: "AVAILABLE"
1: Object
id: ObjectId("5ee277bab0df345e54614b61")
status: "AVAILABLE"
As you can see a restaurant can have multiple tables, obviously.
Now I would like to update the status of a table for which I know the _id. I also know the _id of the restaurant that has the table.
But....I only want to update the status if we have the corresponding tableId and this table has the status 'AVAILABLE'.
My update statement:
const result = await Restaurant.updateOne(
{
_id: ObjectId("5edaaed8d8609c2c47fd6582"),
'tables._id': ObjectId("5ee277bab0df345e54614b61"),
'tables.status': 'AVAILABLE'
},
{ $set: { 'tables.$.status': 'CONFIRMED' } }
);
Guess what happens when I run the update-statement above?
It strangely updates the FIRST table (with the wrong table._id)!
However, when I remove the 'tables.status' filter from the query, it does update the right table:
const result = await Restaurant.updateOne(
{
_id: ObjectId("5edaaed8d8609c2c47fd6582"),
'tables._id': ObjectId("5ee277bab0df345e54614b61")
},
{ $set: { 'tables.$.status': 'CONFIRMED' } }
);
Problem here is that I need the status to be 'AVAILABLE', or else it should not update!
Can anybody point me in the wright direction with this?
according to the docs, the positional $ operator acts as a placeholder for the first element that matches the query document
so you are updating only the first array element in the document that matches your query
you should use the filtered positional operator $[identifier]
so your query will be something like that
const result = await Restaurant.updateOne(
{
_id: ObjectId("5edaaed8d8609c2c47fd6582"),
'tables._id': ObjectId("5ee277bab0df345e54614b61"),
'tables.status': 'AVAILABLE'
},
{
$set: { 'tables.$[table].status': 'CONFIRMED' } // update part
},
{
arrayFilters: [{ "table._id": ObjectId("5ee277bab0df345e54614b61"), 'table.status': 'AVAILABLE' }] // options part
}
);
by this way, you're updating the table element that has that tableId and status
hope it helps
This query works perfectly
{
$or:[{author:this.userId} , {somethingelse:true} ]
}
But when I try:
{
$or:[{author:this.userId} , {sharedwith[this.userId]:true} ]
}
I receive the message
Errors prevented startup:
While processing files with ecmascript (for target os.linux.x86_64): server/main.js:113:43: Unexpected token, expected
, (113:43)
=> Your application has errors. Waiting for file change.
And thats where the comma , in the $or statement is
Help
I guess that you are trying to retrieve all documents for which the current user is the author, or which have been shared with him/her? And therefore that you have structured your documents with a sharedWith field which is a hash map of userId as keys and boolean as value?
Document structure:
{
author: string,
sharedWith: {
<userId1>: boolean
// <userId2>…
}
}
In that case, your MongoDB query should use the dot notation to specify the value of a nested field within sharedWith field:
{
$or: [{
author: string
}, {
"sharedWith.<userId>": boolean
}]
}
To easily create the query with the interpolated value of <userId>, you can use a computed key in your object (ES6 syntax):
{
$or:[{
author: this.userId
} , {
// The query computed key must be in square brackets.
// Specify the field child key using the dot notation within your query.
["sharedwith." + this.userId]: true
}]
}
Or with good old ES5 syntax, similarly to #MichelFloyd's answer:
var query = {
$or: [{
author: this.userId
}]
};
var newCondition = {};
newCondition["sharedWith." + this.userId] = true;
query.$or.push(newCondition);
Note: the above described document structure could conveniently replace the sharedWith hash map by an array (since having a false value for the boolean could simply be replaced by removing the corresponding userId from the array):
{
author: string,
sharedWith: [
<userId1>
// <userId2>…
]
}
In which case the query would simply become:
{
$or:[{
author: this.userId
} , {
// In MongoDB query, the below selector matches either:
// - documents where `sharedWith` value is a string equal to
// the value of `this.userId`, or
// - documents where `sharedWith` value is an array which contains
// an element with the same value as `this.userId`.
sharedwith: this.userId
}]
}
Try building the query as a variable before running it.
let query = { $or: [{ author: this.userId }]};
const sw = sharedwith[this.userId];
query.$or.push({sw: true});
MyCollection.find(query);
I have documents in games collection.Each document is responsible for holding the data that requires to run the game. Here's my document structure
{
_id: 'xxx',
players: [
user:{} // Meteor.users object
hand:[] //array
scores:[]
calls:[]
],
table:[],
status: 'some string'
}
Basically this is a structure of my card game(call-bridge). Now what I want for the publication is that the player will have his hand data in his browser( minimongo ) along with other players user, scores, calls fields. So the subscription that goes down to the browser will be like this.
{
_id: 'xxx',
players: [
{
user:{} // Meteor.users object
hand:[] //array
scores:[]
calls:[]
},
{
user:{} // Meteor.users object
scores:[]
calls:[]
},
// 2 more player's data, similar to 2nd player's data
],
table:[],
status: 'some string'
}
players.user object has an _id property which differentiates the user. and in the meteor publish method, we have access to this.userId which returns the userId who is requesting the data.It means I want the nested hand array of that user whose _id matches with this.userId. I hope this explanations help you write more accurate solution.
What you need to do is "normalize" your collection. Instead of having hand,scores, calls in the players field in the Games collection, what you can do is create a separate collection to hold that data and use the user _id as the "Key" then only reference the user _id in the players field. For example.
Create a GameStats collection(or whichever name you want)
{
_id: '2wiowew',
userId: 1,
hand:[],
scores:[],
calls:[],
}
Then in the Games collection
{
_id: 'xxx',
players: [userId],
table:[],
status: 'some string'
}
So if you want to get the content of the current user requesting the data
GameStats.find({userId: this.userId}).hand
EDIT
They do encourage denormalization in certain situations, but in the code you posted above, array is not going to work. Here is an example from the mongoDB docs.
{
_id: ObjectId("5099803df3f4948bd2f98391"),
name: { first: "Alan", last: "Turing" },
birth: new Date('Jun 23, 1912'),
death: new Date('Jun 07, 1954'),
contribs: [ "Turing machine", "Turing test", "Turingery" ],
views : NumberLong(1250000)
}
To get a specific property from an array element you may write something as in the below line db.games.aggregate([{$unwind:"$players"},{$project:{"players.scores":1}}]); this gives us only the id and scores fields
I need to publish a simplified version of posts to users. Each post includes a 'likes' array which includes all the users who liked/disliked that post, e.g:
[
{
_id: user_who_liked,
liked: 1 // or -1 for disliked
},
..
]
I'm trying to send a simplified version to the user who subscribes an array which just includes his/her like(s):
Meteor.publish('posts', function (cat) {
var _self = this;
return Songs.find({ category: cat, postedAt: { $gte: Date.now() - 3600000 } }).forEach(function (post, index) {
if (_self.userId === post.likes[index]._id) {
// INCLUDE
} else
// REMOVE
return post;
})
});
I know I could change the structure, including the 'likes' data within each user, but the posts are usually designed to be short-lived, to it's better to keep that data within each post.
You need to use this particular syntax to find posts having a likes field containing an array that contains at least one embedded document that contains the field by with the value this.userId.
Meteor.publish("posts", function (cat) {
return Songs.find({
category: cat,
postedAt: { $gte: Date.now() - 3600000 },
"likes._id":this.userId
},{
fields:{
likes:0
}
});
});
http://docs.mongodb.org/manual/tutorial/query-documents/#match-an-array-element
EDIT : answer was previously using $elemMatch which is unnecessary because we only need to filter on one field.
I have an array inside a document of a collection called pown.
{
_id: 123..,
name: pupies,
pups:[ {name: pup1, location: somewhere}, {name: pup2, ...}]
}
Now a user using my rest-service sends the entire first entry as put request:
{name: pup1, location: inTown}
After that I want to update this element in my database.
Therefore I tried this:
var updatedPup = req.body;
var searchQuery = {
_id : 123...,
pups : { name : req.body.name }
}
var updateQuery = {
$set: {'pups': updatedPup }
}
db.pown.update(searchQuery, updateQuery, function(err, data){ ... }
Unfortunately it is not updating anythig.
Does anyone know how to update an entire array-element?
As Neil pointed, you need to be acquainted with the dot notation(used to select the fields) and the positional operator $ (used to select a particular element in an array i.e the element matched in the original search query). If you want to replace the whole element in the array
var updateQuery= {
"$set":{"pups.$": updatedPup}
}
If you only need to change the location,
var updateQuery= {
"$set":{"pups.$.location": updatedPup.location}
}
The problem here is that the selection in your query actually wants to update an embedded array element in your document. The first thing is that you want to use "dot notation" instead, and then you also want the positional $ modifier to select the correct element:
db.pown.update(
{ "pups.name": req.body.name },
{ "$set": { "pups.$.locatation": req.body.location }
)
That would be the nice way to do things. Mostly because you really only want to modify the "location" property of the sub-document. So that is how you express that.