I need to define the mongoose schema for for nested documents which is given below.
Documents:
"Options":[{"Value":["28","30","32","34","36","38","40","42","44","46"],"_id":{"$oid":"5de8427af55716115dd43c8f"},"Name":"Size"},{"Value":["White"],"_id":{"$oid":"5de8427af55716115dd43c8e"},"Name":"Colour"}]
I was declaring like below but its not working.
const Product = new Schema(
{
Options: [{ value: { _id: ObjectId, Name: String } }]
},
{
timestamps: {
createdAt: "createdAt",
updatedAt: "updatedAt"
},
collection: "products"
}
);
Here I need the schema where if i will directly add/update the same document then it will be added.
You need to modify your schema like this :
{
Options: [ new Schema ({ value: [...], _id: Schema.Types.ObjectId, Name: String })]
}
This is the way to create an array of subdocuments with Mongoose. If you don't use the "new Schema" key words, you are actually creating a field with type "Mixed", which needs a different way to handle updates.
You can also omit the _id, it should be added automatically.
You can find more information on subdocument on this page :
https://mongoosejs.com/docs/subdocs.html
...and on mixed type fields : https://mongoosejs.com/docs/schematypes.html#mixed
...which will explain shortly the problem.
{
Options: [ new Schema ({ _id: mongoose.Types.ObjectId(),value: [String], Name: String } })]
}
Related
If you have subdocument arrays, Mongoose automatically creates ids for each one. Example:
{
_id: "mainId"
subDocArray: [
{
_id: "unwantedId",
field: "value"
},
{
_id: "unwantedId",
field: "value"
}
]
}
Is there a way to tell Mongoose to not create ids for objects within an array?
It's simple, you can define this in the subschema :
var mongoose = require("mongoose");
var subSchema = mongoose.Schema({
// your subschema content
}, { _id : false });
var schema = mongoose.Schema({
// schema content
subSchemaCollection : [subSchema]
});
var model = mongoose.model('tablename', schema);
You can create sub-documents without schema and avoid _id. Just add _id: false to your subdocument declaration.
var schema = new mongoose.Schema({
field1: {
type: String
},
subdocArray: [{
_id: false,
field: { type: String }
}]
});
This will prevent the creation of an _id field in your subdoc.
Tested in Mongoose v5.9.10
Additionally, if you use an object literal syntax for specifying a sub-schema, you may also just add _id: false to supress it.
{
sub: {
property1: String,
property2: String,
_id: false
}
}
I'm using mongoose 4.6.3 and all I had to do was add _id: false in the schema, no need to make a subschema.
{
_id: ObjectId
subDocArray: [
{
_id: false,
field: "String"
}
]
}
You can use either of the one
var subSchema = mongoose.Schema({
//subschema fields
},{ _id : false });
or
var subSchema = mongoose.Schema({
//subschema content
_id : false
});
Check your mongoose version before using the second option
If you want to use a predefined schema (with _id) as subdocument (without _id), you can do as follow in theory :
const sourceSchema = mongoose.Schema({
key : value
})
const subSourceSchema = sourceSchema.clone().set('_id',false);
But that didn't work for me. So I added that :
delete subSourceSchema.paths._id;
Now I can include subSourceSchema in my parent document without _id.
I'm not sure this is the clean way to do it, but it work.
NestJS example for anyone looking for a solution with decorators
#Schema({_id: false})
export class MySubDocument {
#Prop()
id: string;
}
Below is some additional information from the Mongoose Schema Type definitions for id and _id:
/**
* Mongoose assigns each of your schemas an id virtual getter by default which returns the document's _id field
* cast to a string, or in the case of ObjectIds, its hexString.
*/
id?: boolean;
/**
* Mongoose assigns each of your schemas an _id field by default if one is not passed into the Schema
* constructor. The type assigned is an ObjectId to coincide with MongoDB's default behavior. If you
* don't want an _id added to your schema at all, you may disable it using this option.
*/
_id?: boolean;
I need some help with MongoDb. I need to check if an object exists in the database. If it's true, then I need to check if this object has a specific element into array (Products). If not, I need to create this object(Order) with this element(Cookie) in to array(Products).
Example data:
Order {
_id: ObjectId("580bc55f54101f1d18152d88"),
code: "AVG223424",
products: [
{
name: "Cookie"
},
{
name: "Soda"
}
]
}
Finally, what is the better implementation?
Assuming you are using a collection with the name 'Orders'
db
.Orders
.update({
code: "12345"
}, {
$addToSet: {
products: {
name: "Cookie"
}
},
$setOnInsert: {
code: "12345"
}
}, {
upsert: true
});
This query looks for a document with the same 'code,' and if found, will add the object '{name: "Cookie"}' if there is no other Object with the same key/val pairs. If the document does not exist, the '$setOnInsert' command will set the specified fields only if a new document is created.
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)
If you have subdocument arrays, Mongoose automatically creates ids for each one. Example:
{
_id: "mainId"
subDocArray: [
{
_id: "unwantedId",
field: "value"
},
{
_id: "unwantedId",
field: "value"
}
]
}
Is there a way to tell Mongoose to not create ids for objects within an array?
It's simple, you can define this in the subschema :
var mongoose = require("mongoose");
var subSchema = mongoose.Schema({
// your subschema content
}, { _id : false });
var schema = mongoose.Schema({
// schema content
subSchemaCollection : [subSchema]
});
var model = mongoose.model('tablename', schema);
You can create sub-documents without schema and avoid _id. Just add _id: false to your subdocument declaration.
var schema = new mongoose.Schema({
field1: {
type: String
},
subdocArray: [{
_id: false,
field: { type: String }
}]
});
This will prevent the creation of an _id field in your subdoc.
Tested in Mongoose v5.9.10
Additionally, if you use an object literal syntax for specifying a sub-schema, you may also just add _id: false to supress it.
{
sub: {
property1: String,
property2: String,
_id: false
}
}
I'm using mongoose 4.6.3 and all I had to do was add _id: false in the schema, no need to make a subschema.
{
_id: ObjectId
subDocArray: [
{
_id: false,
field: "String"
}
]
}
You can use either of the one
var subSchema = mongoose.Schema({
//subschema fields
},{ _id : false });
or
var subSchema = mongoose.Schema({
//subschema content
_id : false
});
Check your mongoose version before using the second option
If you want to use a predefined schema (with _id) as subdocument (without _id), you can do as follow in theory :
const sourceSchema = mongoose.Schema({
key : value
})
const subSourceSchema = sourceSchema.clone().set('_id',false);
But that didn't work for me. So I added that :
delete subSourceSchema.paths._id;
Now I can include subSourceSchema in my parent document without _id.
I'm not sure this is the clean way to do it, but it work.
NestJS example for anyone looking for a solution with decorators
#Schema({_id: false})
export class MySubDocument {
#Prop()
id: string;
}
Below is some additional information from the Mongoose Schema Type definitions for id and _id:
/**
* Mongoose assigns each of your schemas an id virtual getter by default which returns the document's _id field
* cast to a string, or in the case of ObjectIds, its hexString.
*/
id?: boolean;
/**
* Mongoose assigns each of your schemas an _id field by default if one is not passed into the Schema
* constructor. The type assigned is an ObjectId to coincide with MongoDB's default behavior. If you
* don't want an _id added to your schema at all, you may disable it using this option.
*/
_id?: boolean;
var myschema = new Schema({
name: {type:String, default:'fullname'},
subdoc: {
day1: {type:Array, default:[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]},
day2: {type:Array, default:[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]}
}
});
var mymodel = Mongoose.model('mytest',myschema);
//mongoose 3.5.6: find
mymodel.find({},{'name'}, function(err,docs){
logger.info("---> " + docs);
});
results:
---> { _id: 512da190ba48050f2e000001, **subdoc: {}**, name: 'fullname' }
Only name field is requested to be returned, but this function always returns subdoc: {}. Can someone explain this?
use mongodb shell, it looks fine
db.mytests.find({},{"name":1})
{ "_id" : ObjectId("512da190ba48050f2e000001"), "name" : "fullname" }
Then I change the model to:
var myschema = new Schema({
name: {type:String, default:'fullname'},
subdoc: [
day1: {type:Array, default:[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]},
day2: {type:Array, default:[0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0]}
] // **note: not {} here**
})
use the same mongoose api find, the result is just what I expected:
--->{ _id: 512da46fffebd24b30000002, name: 'fullname' }
My questions is: Why field 'subdoc' is returned with the former schema?
According to the docs, it appears as if you are a little bit off.
Example:
// name LIKE john and only selecting the "name" and "friends" fields, executing immediately
MyModel.find({ name: /john/i }, 'name friends', function (err, docs) { })
With that, I would do something like this:
myModel.find( {}, 'name', callback);
Edit
To address your comments: In mongodb console, the proper way to format it would be {'name':1, 'friend':1}. Using:
db.collection.find({}, {'name friend'})
will throw an error. To do this properly, you would do:
db.collection.find({}, {'name':1, 'friend':1})
However, if you prefer this way of field selection, mongoose does allow you to do that as well.
myModel.find({}, {'name':1, 'friend': 1}, callback);
See: API Docs