I have an object in my document like this:
revisions: {
<revisionId>: {
...
someProperty: { ... },
},
...
}
I would like to remove someProperty from every nested object in revisions object (i.e. iterate through all the object revisionId keys). I'm asking because if it's not possible I'd rather convert this to an array than do it on the server and possibly overwrite any updates in the mean time.
I tried $unset but I'm only aware of the $[] operator which only works for arrays e.g.
$unset: {
'revisions.$[].someProperty': 1
}
Thanks
You're almost there:
{ $unset: { someProperty: "" } }
The value doesn't matter from memory
You could then use a cursor to iterate through each doc and remove the unwanted property.
db.collection.find().forEach(<function>)
EDIT: Sorry, realising it's a nested model with arbitrary key for the top level property, makes it more tricky.
t.forEach(function( row) {
var newRevisions = [];
row.revisions.fields.forEach( function( revision ){
delete revision.someProperty;
newRevisions.push(revision);
} )
t.update(
{ _id: row._id },
{ "$set": { "revisions": newRevisions} }
);
});
Huge caveat, totally untested, but should give you starting point.
For each row
For each revision in revisions object
Remove the someProperty property
Set the revisions property back the collection based on _id
Related
I have a very large array, similar to this one:
{
"name":"latest_test",
"value":[
{
"name":"2016-06-27-12Z",
"type":"Folder"
},
{
"name":"2016-06-28-00Z",
"type":"Folder"
},
{
"name":"2016-06-28-12Z",
"type":"Folder"
},
{
"name":"2016-06-29-00Z",
"type":"Folder"
},
{
"name":"2016-06-29-12Z",
"type":"Folder"
}
]
}
I only want to keep the items that have 2016-06-29 in their name. Such that I have a new array that only consists of 2016-06-29-00Z and 2016-06-29-12Z.
I tried to use a filter with #contains(item(), '2016-06-29') but this returns 0.
item() is the entire object for an element in the array. In order to filter on a property have to specify the property also.
Change the filter condition to
#contains(item().name, '2016-06-29')
I have a situation where a model changed at some point in time and I am faced with (for argument sake) half my data liks like this
{
_id: OID,
things: [{
_id:OID,
arm: string,
body: string
}],
other: string
}
and the other half of my data look like this
{
_id: OID,
things: [{
_id:OID,
upper_appendage: string,
body: string
}],
other: string
}
I would like to 'correct' half of the data - so that I DON'T have to accommodate both names for 'arm' in my application code.
I have tried a couple different things:
The first errors
db.getCollection('x')
.find({things:{$exists:true}})
.forEach(function (record) {
record.things.arm = record.things.upper_appendage;
db.users.save(record);
});
and this - which destroys all the other data in
db.getCollection('x')
.find({things:{$exists:true}})
.forEach(function (record) {
record.things = {
upper_appendage.arm = record.things.upper_appendage
};
db.users.save(record);
});
Keeping in mind that there is other data I want to maintain...
How can I do this???
the $rename operator should have worked for this job but unfortunately it doesn't seem to support nested array fields (as of mongodb server 4.2). instead you'd need a forEach like the following:
db.items.find({
things: {
$elemMatch: {
arm: {
$exists: true
}
}
}
}).forEach(function(item) {
for (i = 0; i != item.things.length; ++i)
{
item.things[i].upper_appendage = item.things[i].arm;
delete item.things[i].arm; ;
}
db.items.update({
_id: item._id
}, item);
})
note: i've assumed you want to make all records have upper_appendageand get rid of 'arm' field. if it's the other way you want, just switch things around.
So I have found quite few related posts on SO on how to update a field in a sub array, such as this one here
What I want to achieve is basically the same thing, but updating a field in a subarray dynamically, instead of just calling the field name in the query.
Now I also found how to do that straight in the main object, but cant seem to do it in the sub array.
Code to insert dynamically in sub-object:
_.each(data.data, function(val, key) {
var obj = {};
obj['general.'+key] = val;
insert = 0 || (Documents.update(
{ _id: data._id },
{ $set: obj}
));
});
Here is the tree of what I am trying to do:
Documents: {
_id: '123123'
...
smallRoom:
[
_id: '456456'
name: 'name1'
description: 'description1'
],
[
...
]
}
Here is my code:
// insert a new object in smallRoom, with only the _id so far
var newID = new Mongo.ObjectID;
var createId = {_id: newID._str};
Documents.update({_id: data._id},{$push:{smallRooms: createId}})
And the part to insert the other fields:
_.each(data.data, function(val, key) {
var obj = {};
obj['simpleRoom.$'+key] = val;
console.log(Documents.update(
{
_id: data._id, <<== the document id that I want to update
smallRoom: {
$elemMatch:{
_id : newID._str, <<== the smallRoom id that I want to update
}
}
},
{
$set: obj
}
));
});
Ok, having said that, I understand I can insert the whole object straight away, not having to push every single field.
But I guess this question is more like, how does it work if smallRoom had 50 fields, and I want to update 3 random fields ? (So I would NEED to use the _each loop as I wouldnt know in advance which field to update, and would not want to replace the whole object)
I'm not sure I 100% understand your question, but I think the answer to what you are asking is to use the $ symbol.
Example:
Documents.update(
{
_id: data._id, smallRoom._id: newID._str
},
{
$set: { smallroom.$.name: 'new name' }
}
);
You are finding the document that matches the _id: data._id, then finding the object in the array smallRoom that has an _id equal to newId._str. Then you are using the $ sign to tell Mongo to update that object's name key.
Hope that helps
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.
I am trying to insert nested documents in to a MongoDB using C#. I have a collection called categories. In that collection there must exist documents with 2 array, one named categories and one named standards. Inside those arrays must exist new documents with their own ID's that also contain arrays of the same names listed above. Below is what I have so far but I am unsure how to proceed. If you look at the code what I want to do is add the "namingConventions" document nested under the categories array in the categories document however namingConventions must have a unique ID also.
At this point I am not sure I have done any of this the best way possible so I am open to any and all advice on this entire thing.
namespace ClassLibrary1
{
using MongoDB.Bson;
using MongoDB.Driver;
public class Class1
{
public void test()
{
string connectionString = "mongodb://localhost";
MongoServer server = MongoServer.Create(connectionString);
MongoDatabase standards = server.GetDatabase("Standards");
MongoCollection<BsonDocument> categories = standards.GetCollection<BsonDocument>("catagories");
BsonDocument[] batch = {
new BsonDocument { { "categories", new BsonArray {} },
{ "standards", new BsonArray { } } },
new BsonDocument { { "catagories", new BsonArray { } },
{ "standards", new BsonArray { } } },
};
categories.InsertBatch(batch);
((BsonArray)batch[0]["categories"]).Add(batch[1]);
categories.Save(batch[0]);
}
}
}
For clarity this is what I need:
What I am doing is building a coding standards site. The company wants all the standards stored in MongoDB in a tree. Everything must have a unique ID so that on top of being queried as a tree it can be queried by itself also. An example could be:
/* 0 */
{
"_id" : ObjectId("4fb39795b74861183c713807"),
"catagories" : [],
"standards" : []
}
/* 1 */
{
"_id" : ObjectId("4fb39795b74861183c713806"),
"categories" : [{
"_id" : ObjectId("4fb39795b74861183c713807"),
"catagories" : [],
"standards" : []
}],
"standards" : []
}
Now I have written code to make this happen but the issue seems to be that when I add object "0" to the categories array in object "1" it is not making a reference but instead copying it. This will not due because if changes are made they will be made to the original object "0" so they will not be pushed to the copy being made in the categories array, at least that is what is happening to me. I hope this clears up what I am looking for.
So, based on your latest comment, it seems as though this is the actual structure you are looking for:
{
_id: ObjectId(),
name: "NamingConventions",
categories: [
{
id: ObjectId(),
name: "Namespaces",
standards: [
{
id: ObjectId(),
name: "TitleCased",
description: "Namespaces must be Title Cased."
},
{
id: ObjectId().
name: "NoAbbreviations",
description: "Namespaces must not use abbreviations."
}
]
},
{
id: ObjectId(),
name: "Variables",
standards: [
{
id: ObjectId(),
name: "CamelCased",
description: "variables must be camel cased."
}
]
}
]
}
Assuming this is correct, then the below is how you would insert one of these:
var collection = db.GetCollection("some collection name");
var root = new BsonDocument();
root.Add("name", "NamingConventions");
var rootCategories = new BsonArray();
rootCategories.Add(new BsonDocument
{
{ "id": ObjectId.GenerateNewId() },
{ "name", "Namespaces" },
{ "standards", new BsonArray() }
});
root.Add("categories", rootCategories);
//etc...
collection.Save(root);
Hope that helps, if not, I give up :).
So, I guess I'm confused by what you are asking. If you just want to store the namingConventions documents inside the array, you don't need a collection for them. Instead, just add them to the bson array and store them.
var categoriesCollection = db.GetCollection<BsonDocument>("categories");
var category = new BsonDocument();
var namingConventions = new BsonArray();
namingConventions.Add(new BsonDocument("convention1", "value"));
category.Add("naming_conventions", namingConventions);
categoriesCollection.Insert(category);
This will create a new document for a category, create an array in it called naming_conventions with a single document in it with an element called "convention1" and a value of "value".
I also am not quite sure what you are trying to accomplish. Perhaps if you posted some sample documents in JSON format we could show you the C# code to write documents that match that.
Alternatively, if you wish to discuss your schema, that could also be better done in the context of JSON rather than C#, and once a schema has been settled on then we can discuss how to write documents to that schema in C#.
One thing that didn't sound right in your original description was the statement "in that collection must exist 2 arrays". A collection can only contain documents, not arrays. The documents themselves can contain arrays if you want.
var filter = Builders<CollectionDefination>.Filter.Where(r => r._id== id);
var data = Builders<CollectionDefination>.Update.Push(f=>
f.categories,categoriesObject);
await _dbService.collection.UpdateOneAsync( filter,data);
Note: Make sure embedded document type [Categories] is array.