I have a document like this:
[ { _id: 55535305c6d17454276beba1,
name: 'Localhost',
tables: [{ chairs:[{
data:[{
}]
}]
}]
}
]
I want to update/insert new data in the data document.
You can do something along these lines for your example:
db.collectionName.update(
{_id: 55535305c6d17454276beba1},
{$set: {"tables.chairs.data" : [{somethingHere:1}] }}
);
You can update individual elements in the data array by using this syntax:
db.collectionName.update(
{_id: 55535305c6d17454276beba1},
{$set: {"tables.chairs.data.0" : {somethingHere:2} }}
);
This link provides some additional examples:
Updating Value of Array Element in MongoDB
Related
I'd like to be able to pull a document by id from a triple nested array of documents. DB looks something like this:
[{
type: "Foods",
fruit: [{
name: "Apple",
kinds: [{
name: "Red Delicious"
details: [{
_id: ObjectId("123123123"),
colors: ["red", "yellow"]
}]
}]
}]
}]
I'd like to be able to pull the document with the _id: 123123123. I've tried many different ways, but it always says it matches, but won't modify the document.
I've tried:
db.stuff.update({}, {$pull: {fruits: {kinds: {details: {_id: "123123123"}}}}}),
db.stuff.update({}, {$pull: {"fruits.kinds.details' : {_id: "123123123"}}}),
db.stuff.update({}, {$pull: {"fruits.$[].kinds.$[].details' : {_id: "123123123"}}})
But everytime it matches, but won't delete the document.
Please help.
The last attempt is correct however you need to fix two things: fruit instead of fruit (according to your sample data) and types needs to match so you have to convert string to ObjectId
db.stuff.update({}, {$pull: {"fruit.$[].kinds.$[].details' : {_id: mongoose.Types.ObjectId("123123123")}}})
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.
A question if I want to update all documents embedded in a document, how could I do? because when you run the following command
.update({'sites':{$elemMatch:{'status':true}}},{$set:{'sites.$.status': false}},{multi:true})
only the first found embedded document is updated
documents example:
{
'_id': 1,
sites: [
{'status':true,'url':'http://google.com'},
{'status':true,'url':'https://university.mongodb.com'},
{'status':true,'url':'https://docs.mongodb.org'}
]}
This isn't possible, the closes you can get is to update the entire element. e.g.:
db.test.update({
_id: 1
},
{
$set: {
sites: [
{'status':true,'url':'http://1.example.com'},
{'status':true,'url':'http://2.example.com'},
{'status':true,'url':'http://3.example.com'},
]
}
})
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.
I have the following data in MongoDB (simplified for what is necessary to my question).
{
_id: 0,
actions: [
{
type: "insert",
data: "abc, quite possibly very very large"
}
]
}
{
_id: 1,
actions: [
{
type: "update",
data: "def"
},{
type: "delete",
data: "ghi"
}
]
}
What I would like is to find the first action type for each document, e.g.
{_id:0, first_action_type:"insert"}
{_id:1, first_action_type:"update"}
(It's fine if the data structured differently, but I need those values present, somehow.)
EDIT: I've tried db.collection.find({}, {'actions.action_type':1}), but obviously that returns all elements of the actions array.
NoSQL is quite new to me. Before, I would have stored all this in two tables in a relational database and done something like SELECT id, (SELECT type FROM action WHERE document_id = d.id ORDER BY seq LIMIT 1) action_type FROM document d.
You can use $slice operator in projection. (but for what you do i am not sure that the order of the array remain the same when you update it. Just to keep in mind))
db.collection.find({},{'actions':{$slice:1},'actions.type':1})
You can also use the Aggregation Pipeline introduced in version 2.2:
db.collection.aggregate([
{ $unwind: '$actions' },
{ $group: { _id: "$_id", first_action_type: { $first: "$actions.type" } } }
])
Using the $arrayElemAt operator is actually the most elegant way, although the syntax may be unintuitive:
db.collection.aggregate([
{ $project: {first_action_type: {$arrayElemAt: ["$actions.type", 0]}
])