I have a collection like this
{
_id: "qex6zPLgigq4KGpFP",
active: true,
name: "event name",
questions: [{
_id: "cff4cc7f1ae67282f1ea142b",
createdBy: "izRFAkhxgemihkRMF",
likes: 2
}, {
_id: "2cf23241ca456703f50a9ce4",
createdBy: "izRFAkhxgemihkRMF",
likes: 0
}]
}
and I initialize my collection in my Meteor application like this:
Events = new Mongo.Collection("events");
Now I want to remove a subdocument from the 'questions' array and it works in the shell with
db.events.update({_id:"qex6zPLgigq4KGpFP"}, {$pull: {'questions': {_id:"cff4cc7f1ae67282f1ea142b"}}})
but NOT in Meteor by calling
Events.update({_id:"qex6zPLgigq4KGpFP"}, {$pull: {'questions': {_id:"cff4cc7f1ae67282f1ea142b"}}})
The return value is always '1', but the document is still there.
It's confusing. Any ideas?
Related
I am new to MongoDB and I need help with one basic operation that I am trying. Below is how my mongo collection is structured,
{
id: "<some_id>",
field1: ["value1", "value2", "value3"],
field2:[
field-a {
id: <some_id>,
field-a-1: <some_string>,
field-a-2: [<some_value>, <some_value>]
},
field-b {
id: <some_id>,
field-b-1: <some_string>,
field-b-2: [<some_value>, <some_value>]
},
field-c {
id: <some_id>,
field-c-1: <some_string>,
field-c-2: [<some_value>, <some_value>]
},
field-d {
id: <some_id>,
field-d-1: <some_string>,
field-d-2: [<some_value>, <some_value>]
},
]
}
I want to get the document from “field2" which has id === <requested_id>
I am trying it via mongo shell and below is the query that I am using.
db.posts.find({'field2.id': {$eq:'<some_id>'}})
It is not working. It returns all the documents of the field2 array and I don’t want that.
so i have following problem.
I have a mongoDB collection and a corresponding mongoose model which looks like this.
export const ListItemSchema = new Schema<ListItemSchema>({
title: { type: String, required: true },
parentId: { type: Schema.Types.ObjectId, required: false },
});
export const TestSchema = new Schema<Test>(
{
title: { type: String, required: true },
list: { type: [ListItemSchema], required: false },
}
);
As you can see, my TestSchema holds an Array of ListItems inside -> TestSchema is also my Collection in MongoDB.
Now i want to query only my ListItems from a Test with a specific ID.
Well that was not that big of a problem at least from the MongoDB side.
I use MongoDB Aggregation Framework for this and call my aggregation inside a custom Resolver.
Here is the code to get an array of only my listItems from a specific TestModel
const test = TestModel.aggregate([
{$match: {_id: id}},
{$unwind: "$list"},
{
$match: {
"list.parentId": {$eq: null},
},
},
{$replaceRoot: {newRoot: "$list"}},
]);
This is the result
[ { _id: randomId,
title: 't',
parentId: null },
{ _id: randomId,
title: 'x'
parentId: null
} ]
The Query to trigger the resolver looks like this and is placed inside my Test Type Composer.
query getList {
test(testId:"2f334575196fe042ea83afbf", parentId: null) {
title
}
}
So far so good... BUT! Ofc my query will fail or will result in a not so good result^^ because GraphQL expects data based on the Test-Model but receives a completely random array.
So after a lot of typing here is the question:
How do i have to change my query to receive the list array?
Do i have to adjust the query or is it something with mongoose?
i really stuck at this point so any help would be awesome!
Thanks in advance :)
I'm not sure if I understood your issue correctly.
In your graphql, try to leave out exclamation mark(!) from the Query type.
something like :
type Query {
test: TestModel
}
instead of
type Query {
test: TestModel!
}
then you'll get the error message in console but still be able to receive any form of data.
I have the following schema:
{
_id: objectID('593f8c591aa95154cfebe612'),
name: 'test'
businesses: [
{
_id: objectID('5967bd5f1aa9515fd9cdc87f'),
likes: [objectID('595796811aa9514c862033a1'), objectID('593f8c591ba95154cfebe790')]
}
{
_id: objectID('59579ff91aa9514f600cbba6'),
likes: [objectID('693f8c554aa95154cfebe146'), objectID('193f8c591ba95154cfeber790')]
}
]
}
I need to update "businesses.likes" where businesses._id equal to a center value and where businesses.likes contains certain objectID.
If the objectID exists in the array, I want to remove it.
This is what I have tried and didn't work correctly, because $in is searching in all the subdocuments, instead of the only subdocument where businesses._id = with my value:
db.col.update(
{ businesses._id: objectID('5967bd5f1aa9515fd9cdc87f'), 'businesses.likes': {$in: [objectID('193f8c591ba95154cfeber790')]}},
{$pull: {'businesses.$.likes': objectID('193f8c591ba95154cfeber790')}}
)
Any ideas how how I can write the query? Keep in mind that businesses.likes from different businesses can have the same objectID's.
I'm trying to get all documents in a collection based on a subdocument array values. This is my data structure in the collection i'm seeking:
{
_id: ObjectId('...'),
name: "my event",
members:
[
{
_id: ObjectId('...'),
name: "family",
users: [ObjectId('...'),ObjectId('...'),ObjectId('...')]
},
{
_id: ObjectId('...'),
name: "work",
users: [ObjectId('...'),ObjectId('...'),ObjectId('...')]
}
]
}
I should point out that the schema of these objects are defined like so:
Events:
{
name: { type: String },
members: {type: [{ type: ObjectId, ref: 'MemberGroup' }], default:[] }
}
MemberGroup:
{
name: { type: String },
users: [{type: mongoose.Schema.Types.ObjectId, ref: 'User'}]
}
and of course User is just an arbitrary object with an id.
What i'm trying to fetch: i want to retrieve all events which has a specific user id in its member.users field.
i'm not sure if its event possible in a single call but here is what i've tried:
var userId = new mongoose.Schema.ObjectId('57d9503ef10d5ffc08d6b8cc');
events.find({members: { $elemMatch : { users: { $in: [userId]} } }})
this syntax work but return no elements even though i know there are matching elements (using robomongo to visualize the db)
So after a long search in stackoverflow i came across the good answare here:
MongoDB: How to find out if an array field contains an element?
my query changed to the following which gave me my desired result:
var userId = new mongoose.Schema.ObjectId('57d9503ef10d5ffc08d6b8cc');
events.find({}, {members: { $elemMatch : { users: { $eq: userId} } }})
notice the use of the second find parameter to specify the query limit instead of the first one (which is odd)
Suppose, I have the following database:
{
_id: 1,
name: 'Alice',
courses: [
{
_id: 'DB103',
credits: 6
},
{
_id: 'ML203',
credits: 4
}
]
},
{
_id: 2,
name: 'Bob',
courses: []
}
I now want to 'upsert' the document with the course id 'DB103' in both documents. Although the _id field should remain the same, the credits field value should change (i.e. to 4). In the first document, the respective field should be changed, in the second one, {_id: 'DB103', credits: 4} should be inserted into the courses array.
Is there any possibility in MongoDB to handle both cases?
Sure, I could search with $elemMatch in courses for 'DB103' and if I haven't found it, insert, otherwise update the value. But these are two steps and I would like to do both in just one.