Actually have 2 documents: Histories and Subsidiaries, but I forgot add to Histories the subsidiary name.
Histories Document:
{
"_id" : ObjectId("59480f91ba4d070b882ff924"),
"subsidiary" : ObjectId("5947fdf3ba4d070b882ff851"),
"campaignTitle" : "Prueba Autoredeeem",
"campaignId" : ObjectId("5948004fba4d070b882ff886"),
}
Subsidiary Document
{
"_id" : ObjectId("5947fdf3ba4d070b882ff851"),
"loginId" : 50174,
"name" : "Sucursal Alpha",
}
Now I need update History Document, add a "subsidiaryName" field with "Subsidiary.name" value from Subsidiary Document
This is my first aproach:
db.getCollection('couponredeemhistories')
.updateMany({}, {$set: {subsidiaryName:
db.getCollection('subsidiaries')
.findOne({"_id": ObjectId('5947fdf3ba4d070b882ff851')}, {_id: 0,name: 1})}})
But, the result gives me an Object inside subsidiaryName, instead flat text.
{
"_id" : ObjectId("59480f91ba4d070b882ff924"),
"subsidiary" : ObjectId("5947fdf3ba4d070b882ff851"),
"campaignDescription" : "",
"campaignTitle" : "Prueba Autoredeeem",
"campaignId" : ObjectId("5948004fba4d070b882ff886"),
"subsidiaryName" : {
"name" : "Sucursal Alpha"
}
}
Then, I have 2 problems:
How to set only flat text value to subsidiaryName field?
R: Add .name to project for get flat text
How to set .findOne() "id" param for current document instead ObjectId('HARD CODE')?
R: Iterate with forEach Cursor
IMPORTANT LIMITS: this is for MongoDB Shell (MongoDB 3.4)
Thank you, please support me for fix any language issues on this question.
Updated Answers thanks to #Astro:
db.getCollection('couponredeemhistories').find()
.forEach(function(doc){
if(doc.subsidiary !== undefined){
doc.subsidiaryName = db.getCollection('subsidiaries').findOne({'_id': doc.subsidiary}, {_id: 0, name: 1}).name;
db.getCollection('couponredeemhistories').save(doc);
}
})
Try this:
db.getCollection('couponredeemhistories')
.updateMany({}, {$set: {subsidiaryName:
db.getCollection('subsidiaries')
.findOne({"_id": ObjectId('5947fdf3ba4d070b882ff851')}, {_id: 0,name: 1}).name}})
Related
I searched for similar questions but couldn't find any. Feel free to point me in their direction.
Say I have this data:
{ "_id" : ObjectId("5694c9eed4c65e923780f28e"), "name" : "foo1", "attr" : "foo" }
{ "_id" : ObjectId("5694ca3ad4c65e923780f290"), "name" : "foo2", "attr" : "foo" }
{ "_id" : ObjectId("5694ca47d4c65e923780f294"), "name" : "bar1", "attr" : "bar" }
{ "_id" : ObjectId("5694ca53d4c65e923780f296"), "name" : "bar2", "attr" : "bar" }
If I want to get the latest record for each attribute group, I can do this:
> db.content.aggregate({$group: {_id: '$attr', name: {$last: '$name'}}})
{ "_id" : "bar", "name" : "bar2" }
{ "_id" : "foo", "name" : "foo2" }
I would like to have my data grouped by attr and then sorted by _id so that only the latest record remains in each group, and that's how I can achieve this. BUT I need a way to avoid naming all the fields that I want in the result (in this example "name") because in my real use case they are not known ahead.
So, is there a way to achieve this, but without having to explicitly name each field using $last and just taking all fields instead? Of course, I would sort my data prior to grouping and I just need to somehow tell Mongo "take all values from the latest one".
See some possible options here:
Do multiple find().sort() queries for each of the attr values you
want to search.
Grab the original _id of the $last doc, then do a findOne() for each of those values (this is the more extensible option).
Use the $$ROOT system variable as shown here.
This wouldn't be the quickest operation, but I assume you're using this more for analytics, not in response to a user behavior.
Edited to add slouc's example posted in comments:
db.content.aggregate({$group: {_id: '$attr', lastItem: { $last: "$$ROOT" }}}).
Let's say i want to return the latest inserted document from the subdocument. I want to be able to return the second record within the tags array w/ the _id of 54a1845def7572cd0e3fe288
So I far I have this query but it returns all values in the tags array.
db.modules.findOne({_id:"ui","svn_branches.branch":"Rocky"},{"svn_branches.$":1})
Mongodb array:
{
"_id" : "ui",
"svn_branches" : [
{
"updated_at" : ISODate("2013-06-12T20:48:17.297Z"),
"branch" : "Rocky",
"revision" : 0,
"tags" : [
{
"_id" : ObjectId("54a178b8ef7572d30e3fe288"),
"commit_message" : "r277 | ssmith | 2015-02-11 17:43:23 -0400 (Wed, 11 Feb 2015)",
"latest_tag" : "20150218r1_6.32_abc",
"revision" : 1,
"tag_revision_number" : "280",
"updated_at" : ISODate("2015-02-18T19:54:54.062Z")
},
{
"_id" : ObjectId("54a1845def7572cd0e3fe288"),
"commit_message" : "r271 | sam | 2dskjh\n",
"latest_tag" : "20150218r2_6.32_abc",
"revision" : 2,
"tag_revision_number" : "281",
"updated_at" : ISODate("2015-02-19T19:54:54.062Z")
}
]
}
]
}
Simple Solution
Let say we have a category as a document and items as a subdocument.
// find document from collection
const category = await Category.findOne({ _id:'$hec453d235xhHe4Y' });
// fetch last index of sub-document
const lastItemIndex = category.items.length - 1;
// here is the last item of sub-document
console.log(category.items[lastItemIndex]);
as mongodb inserted the latest sub-document at last index, so we need to find the last index for the latest sub-doc.
Queries in MongoDB do not return subdocuments (or, as in your case, subdocuments of subdocuments). They match and return the the documents in the collection. The documents' shape can be changed a bit by projection, but it's limited. If you want to find the latest tag commonly, you probably want to make your documents represent tags. Having an array in an array is generally a bad idea in MongoDB, too.
If this is an uncommon operation, and one that doesn't need to be particularly fast, you can use an aggregation:
db.modules.aggregate([
{ "$unwind" : "$svn_branches" },
{ "$unwind" : "$svn_branches.tags" },
{ "$sort" : { "svn_branches.tags.updated_at" : -1 } },
{ "$group" : { "_id" : "$_id", "latest_tag" : { "$first" : "$svn_branches.tags" } } }
])
I needed to find the last entry of subdocuments and I managed to make it to work with the $slice projection operator: mondodb.com > $slice (projection)
db.modules.find({_id:'ui', 'svn_branches.branch':'Rocky'},
{ 'svn_branches.tags': {$slice:-1} } )
I had only one level, if this doesn't work, please let me know.
Because of a weird bug in my code, I have a collection with field names which are stricly numbers (ex: 34344,54675,34356).
Now I try to move these fields values to another fields (ex: name,email,etc) but when I run the update command:
db.collection.find({"id_field" : 1996}).forEach(function (elem) {db.collection.update({_id: elem._id},{$set: {name: elem.36536}});});
All I get is an error:
SyntaxError: Unexpected number
How should I handle it? I already tried with elem[36536] instead elem.36536 but without success.
if I got your problem right, this code might help you:
db.collection.find({"id_field" : 1996}).forEach(function (elem)
{
var value = elem['36536'];
db.collection.update({_id: elem._id},{$set: {name: value}});
});
If your document is like this
{
"_id" : 1,
"elem" : {
"123" : "barno",
"456" : "foo#gmail.com"
}
}
you can $rename the key document.
db.d.update({"_id" : 1},{$rename:{'elem.123':'elem.name','elem.456':'elem.email'}})
Result:
{
"_id" : 1,
"elem" : {
"name" : "barno",
"email" : "foo#gmail.com"
}
}
Let me start by saying I'm sorry if this has been answered, but I can't get other questions on this site to fit my needs and, more importantly, work.
I have the below example document, with a subdocument of 'address':
{
"_id" : ObjectId("....")
,"addresses" :
[{
"start" : ISODate("1973-07-10T00:11:51.111Z")
,"value" : "123 long road"
}]
}
What I need to do is to close the existing address record with an end attribute, and add a new line for the new address with a new start and value attribute. Eventually, I'll need to do this again so the code needs to update the subdocument record where end does not exist.
The below code does not work, but it's about as far as I can get:
db.sites.update(
{"_id" : ObjectId("....")
, "addresses.end" : {"$exists" : false}}
,{"$set": {"addresses.$.end" : "fdsa"}});
This gives the error:
Cannot apply the positional operator without a corresponding query field containing an array.
Can anyone point me in the right direction?
Juste replace in your query "addresses.end" : {"$exists" : false} with:
addresses: {$elemMatch: {end: {$exists: false}}}
Your address field is poorly defined. you need make it a subdocument or an array of subdocuments. ie {
"_id" : ObjectId("....")
,"addresses" :
[
{
"start" : ISODate("1973-07-10T00:11:51.111Z")
,"value" : "123 long road"
}
]
}
your query should then work!
I think that the Query should be more specific
**Updated **
db.sites.update ( {"_id" : ObjectId("...."), addresses: { "$elemMatch" : { end:{$exists : false}} } }, {"$set": {"addresses.$.end" : "fdsa"}});
db.sites.find()
results:
{
"_id" : ObjectId("53df93da560b7815e1237934"),
"addresses" : [
{
"start" : ISODate("1973-07-10T00:11:51.111Z"),
"value" : "123 long road",
"end" : "fdsa"
}
]
}
but you can update only one
Take a look http://docs.mongodb.org/manual/reference/operator/projection/positional/#proj.S
You can t update more element in Array https://jira.mongodb.org/browse/SERVER-1243
I have a DB structure like below:
{
"_id" : 1,
"comments" : [
{
"_id" : 2,
"content" : "xxx"
}
]
}
I update a new subdocument in the comments feild. It is OK.
db.test.update(
{"_id" : 1, "comments._id" : 2},
{$push : {"comments.$.comments" : {_id : 3, content:"xxx"}}}
)
after that the DB structure:
{
"_id" : 1,
"comments" : [
{
"_id" : 2,
"comments" : [
{
"id" : 3,
"content" : "xxx"
}
],
"content" : "xxx"
}
]
}
But when I update a new subdocument in the comment field that _id is 3, There is a error:
db.test.update(
{"_id" : 1, "comments.comments.id" : 3},
{$push : {"comments.comments.$.comments" : {id : 4, content:"xxx"}}}
)
error message:
can't append to array using string field name: comments
Well, it makes total sense if you think about it. MongoDb has the advantage and the disadvantage of solving magically certain things.
When you query the database for a specific regular field like this:
{ field : "value" }
The query {field:"value"} makes total sense, it wouldn't in case value is part of an array but Mongo solves it for you, so in case the structure is:
{ field : ["value", "anothervalue"] }
Mongo iterates through all of them and matches "value" into the field and you don't have to think about it. It works perfectly.. at only one level, because it's impossible to guess what you want to do if you have multiple levels
In your case the first query works because it's the case in this example:
db.test.update(
{"_id" : 1, "comments._id" : 2},
{$push : {"comments.$.comments" : {_id : 3, content:"xxx"}}}
)
Matches _id in the first level, and comments._id at the second level, it gets an array as a result but Mongo is able to solve it.
But in the second case, think what you need, let's isolate the where clause:
{"_id" : 1, "comments.comments.id" : 3},
"Give me from the main collection records with _id:1" (one doc)
"And comments which comments inside have and id=3" (array * array)
The first level is solved easily, comments.id, the second is not possible due comments returns an array, but one more level is an array of arrays and Mongo gets an array of arrays as a result and it's not possible to push a document into all the records of the array.
The solution is to narrow your where clause to obtain an unique document in comments (could be the first one) but it's not a good solution because you never know what is the position of the document you're looking for, using the shell I think the only option to be accurate is to do it in two steps. Check this query that works (not the solution anyway) but "solves" the multiple array part fixing it to the first record:
db.test.update(
{"_id" : 1, "comments.0.comments._id" : 3},
{$push : {"comments.0.comments.$.comments" : {id : 4, content:"xxx"}}}
)