I have two collection:
// Profile
{
_id: "12345",
name: "max",
country: "IT"
}
// Association
{
_id: "43234",
idclub: "1000",
state: "0"
}
I want to insert a Profile on Association without searching it.
In my code i search for an Association but i don't have the object Profile in that moment, i just have its "id".
Is it possible to perform some kind of insert on collection A retrieving on the fly the object of collection B given it's own ID?
And then, is this a recurring practice? As i can find nothing it seems not properly the best way...
Thanks
Use findAndModify operator
db.createCollection("Association");
db.Association.insert({ _id : "43234", idclub:"1000",state:"0"});
db.Association.findAndModify({
query:{ _id:"43234" },
update:{ $set:{ "profile":{ _id:"12345","name":"max","country":"IT" } } }
});
db.Association.find();
{"_id" : "43234", "idclub" : "1000", "state" : "0", "profile" : { "_id" :
"12345", "name" : "max", "country" : "IT" } }
Related
I have a record in database:
{
"name" : "user",
"number":"09xxxxxxx21",
"pc" : [{
"pcId" : "1",
"pcName" : "Desktop",
"pcOwner" : "user1"
}, {
"pcId" : "2",
"pcName" : "Laptop",
"pcOwner" : "user1"
}
]}
}
Using mongo find query I'm able to get record when giving name but I want to fetch record based on pcId.
I think you were looking for something like this.
https://mongoplayground.net/p/LsUCVSj_7_e
db.collection.find({
"pc.pcId": "12"
})
This works perfect.
Try this one:
db.collection.find({"pc.pcId": "2"})
As pcId is the child element of pc you need to refer to the parent first to reach that element.
for reference: https://mongoplayground.net/p/uWD9tPPhupR
I am trying to construct a Mongodb query to return a field value. My JSON looks like this:
"question" : "Global_Deployment",
"displayOrder" : 1,
"answerOptions" : {
"fieldId" : "1001",
"fieldType" : "radiobutton",
"fieldName" : "Global Deployment?",
"fieldLabel" : "Global Deployment?",
"helpText" : "Help will go here",
"emailTagFormControl" : "Global_Deployment?",
"source" : "custom",
"status" : "active",
"required" : "true",
"multiSelect" : "false",
"purgeFlag" : "false",
"enableAuditTrack" : "false",
"fields" : [],
"fieldValue" : "Yes",
"options" : [
{
"optionName" : "Yes"
},
{
"optionName" : "No"
}
],
"comments" : {
"commentId" : "C1001",
"commentDetails" : []
}
My query to reach the field with the fieldName "Global Deployment" is this:
db.getCollection('requests').find({"sections.questions.answerOptions.fieldName":"Global Deployment?"})
What I want to know is what to add to this query to return the value of "fieldValue", which is on a different line in the JSON. I am new to Mongodb. Any help would be greatly appreciated.
1) If you've multiple documents in DB with "fieldName" : "Global Deployment?", then .find() would return all the matching documents i.e; in the output what you get is an array of documents then you need to iterate through the array to get answerOptions.fieldValue for each document, Check the below scenario, as I've explained there are chances of getting multiple documents if "sections.questions.answerOptions.fieldName" is not an unique field.
db.getCollection('requests').find({"sections.questions.answerOptions.fieldName":"Global Deployment?"}, {'sections.questions.answerOptions.fieldValue':1})
Output of find :
/* 1 */
[{
"_id" : ObjectId("5d4e19826e173840500f5674"),
"answerOptions" : {
"fieldValue" : "Yes"
}
},
/* 2 */
{
"_id" : ObjectId("5d4e19826e073840500f5674"),
"answerOptions" : {}
}]
If you only need documents which has fieldValue in it then do this :
db.getCollection('requests').find({"sections.questions.answerOptions.fieldName":"Global Deployment?", 'sections.questions.answerOptions.fieldValue':{$exists: true}}, {'answerOptions.fieldValue':1})
Ok now you've array of documents then do iterate thru each to retrieve your value, check this mongoDB cursor tutorial .
2) If you think fieldName is unique across collection, then you can use .findOne() , which would exactly return one document (In case if you've multiple matching documents it would return first found doc) :
db.getCollection('requests').findOne({"sections.questions.answerOptions.fieldName":"Global Deployment?"}, {'sections.questions.answerOptions.fieldValue':1})
Output of findOne :
{
"_id" : ObjectId("5d4e19826e173840500f5674"),
"answerOptions" : {
"fieldValue" : "Yes"
}
}
If you see .find({},{}) has two arguments, second one is called projection which literally be useful if you want to retrieve only required fields in the response, By default mongoDB will return the entire document what ever you've posted in the question will be retrieved, Data in mongoDB flows as JSON's so operating will be similar to using JSON's, Here you can retrieve the required fields out of result, but for best use of network efficiency if you don't need entire document you'll only get the required fields using projection.
You can specify the second condition separated by comma. Either you are trying to filter data with $and or with $or
With simple approach:
{"sections.questions.answerOptions.fieldName":"Global Deployment?","sections.questions.answerOptions.fieldValue":"Yes" }
By using $and method:
.find(
{
$and: [
{"sections.questions.answerOptions.fieldName":"Global Deployment?"},
{"sections.questions.answerOptions.fieldValue":"Yes"}
]
}
)
Same way you can use $or method. Just replace $and with $or.
Edit:
If you want to retrieve specific value (in your case fieldValue), query would be:
db.getCollection('requests').find({
"sections.questions.answerOptions.fieldName":"Global Deployment?"
}).map(function(item){
return item.fieldValue
})
The correct answer here is the method .distinct() (docs)
In your case try it like this:
db.getCollection('requests').find({"sections.questions.answerOptions.fieldName":"Global Deployment?"}).distinct('fieldValue');
That will return only the value you want.
If you use findOne you can use dot notation.
For example, if we start with creating a collection to test using the following to get close to your sample:
db.stackOverflow.insertOne({
sections: {
questions: {
question: "Global_Deployment",
displayOrder: 1,
answerOptions: {
fieldId: "1001",
fieldType: "radiobutton",
fieldName: "Global Deployment?",
fieldLabel: "Global Deployment?",
helpText: "Help will go here",
emailTagFormControl: "Global_Deployment?",
source: "custom",
status: "active",
required: "true",
multiSelect: "false",
purgeFlag: "false",
enableAuditTrack: "false",
fields: [],
fieldValue: "Yes",
options: [
{
optionName: "Yes",
},
{
optionName: "No",
},
],
comments: {
commentId: "C1001",
commentDetails: [],
},
},
},
},
})
then, this query will return "Yes".
db.stackOverflow.findOne({}).sections.questions.answerOptions.fieldValue
In my database.collection i.e. db.blog.posts I am trying to add a key and value that itself has multiple keys and values.
Current collection:
db.blog.posts.findOne()
"title":"blog posts"
I tried using $set, $push but nothing seems to work.
This also didn't work when I tried adding single collection:
db.blog.posts.updateOne({"title":"blog posts"}, {"$set":{"comments":[{"comment":"good post", "author":"john","votes":0}]}})
Nor insertOne instead of updateOne and I even tried with:
var myEmployee=[
{"comment":"good post", "author":"john", "votes":0},
{"comment":"i thought it was too short", "author":"claire","votes":3},
{"comment":"free watches", "author":"claire","votes":-1},
];
db.blog.posts.insert(myEmployee)
This is what I want:
"title" : "A blog post",
"comments" : [
{
"name" : "joe",
"email" : "joe#example.com",
"content" : "nice post."
},
{
"name" : "bob",
"email" : "bob#example.com",
"content" : "good post."
}
]
The updateOne command you have should have created an array for comments with a single entry. If you wanted multiple entries, you can just add multiple objects to the array in the update. The $set operator will change the value of the key to what you set as the second parameter.
db['blog.posts'].updateOne({"title":"blog posts"}, {
"$set": {
"comments":[
{
"name" : "joe",
"email" : "joe#example.com",
"content" : "nice post."
},
{
"name" : "bob",
"email" : "bob#example.com",
"content" : "good post."
}
]
}
})
If you want to add additional items to the comments, this can be done with $push. The $push operator adds to the array.
db['blog.posts'].updateOne({"title":"blog posts"}, {
"$push": {
"comments": {
"comment": "good post",
"author": "john",
"votes": 0
}
}
})
Docs for $set
Docs for $push
NB the examples above are for a collection named 'blog.posts' rather than a database named 'blog' and a collection names 'posts'. Ideally, brackets should be used for the property accessor where the collection name is not a valid JavaScript identifier although the dot notation in the question still works.
I have a collection :
gStats : {
"_id" : "id1",
"criteria" : ["key1":"value1", "key2":"value2"],
"groups" : [
{"id":"XXXX", "visited":100, "liked":200},
{"id":"YYYY", "visited":30, "liked":400}
]
}
I want to be able to update a document of the stats Array of a given array of criteria (exact match).
I try to do this on 2 steps :
Pull the stat document from the array of a given "id" :
db.gStats.update({
"criteria" : {$size : 2},
"criteria" : {$all : [{"key1" : "2096955"},{"value1" : "2015610"}]}
},
{
$pull : {groups : {"id" : "XXXX"}}
}
)
Push the new document
db.gStats.findAndModify({
query : {
"criteria" : {$size : 2},
"criteria" : {$all : [{"key1" : "2015610"}, {"key2" : "2096955"}]}
},
update : {
$push : {groups : {"id" : "XXXX", "visited" : 29, "liked" : 144}}
},
upsert : true
})
The Pull query works perfect.
The Push query gives an error :
2014-12-13T15:12:58.571+0100 findAndModifyFailed failed: {
"value" : null,
"errmsg" : "exception: Cannot create base during insert of update. Cause
d by :ConflictingUpdateOperators Cannot update 'criteria' and 'criteria' at the
same time",
"code" : 12,
"ok" : 0
} at src/mongo/shell/collection.js:614
Neither query is working in reality. You cannot use a key name like "criteria" more than once unless under an operator such and $and. You are also specifying different fields (i.e groups) and querying elements that do not exist in your sample document.
So hard to tell what you really want to do here. But the error is essentially caused by the first issue I mentioned, with a little something extra. So really your { "$size": 2 } condition is being ignored and only the second condition is applied.
A valid query form should look like this:
query: {
"$and": [
{ "criteria" : { "$size" : 2 } },
{ "criteria" : { "$all": [{ "key1": "2015610" }, { "key2": "2096955" }] } }
]
}
As each set of conditions is specified within the array provided by $and the document structure of the query is valid and does not have a hash-key name overwriting the other. That's the proper way to write your two conditions, but there is a trick to making this work where the "upsert" is failing due to those conditions not matching a document. We need to overwrite what is happening when it tries to apply the $all arguments on creation:
update: {
"$setOnInsert": {
"criteria" : [{ "key1": "2015610" }, { "key2": "2096955" }]
},
"$push": { "stats": { "id": "XXXX", "visited": 29, "liked": 144 } }
}
That uses $setOnInsert so that when the "upsert" is applied and a new document created the conditions specified here rather than using the field values set in the query portion of the statement are used instead.
Of course, if what you are really looking for is truly an exact match of the content in the array, then just use that for the query instead:
query: {
"criteria" : [{ "key1": "2015610" }, { "key2": "2096955" }]
}
Then MongoDB will be happy to apply those values when a new document is created and does not get confused on how to interpret the $all expression.
So, what I'm trying to do is query all documents that have a City of 'Paris' and a State of 'France'. I need to do some kind of join, but I haven't been able to figure out how to construct it.
I'm using the c# driver, but I'll gladly accept help using any method.
{
"_id" : ObjectId("519b407f3c22a73a7c29269f"),
"DocumentID" : "1",
"Meta" : [{
"Name" : "City",
"Value" : "Paris",
}, {
"Name" : "State",
"Value" : "France",
}
}]
}
{
"_id" : ObjectId("519b407f3c22a73a7c29269g"),
"DocumentID" : "2",
"Meta" : [{
"Name" : "City",
"Value" : "Paris",
}, {
"Name" : "State",
"Value" : "Texas",
}
}]
}
The $elemMatch operator is used to indicate that all the conditions within it must be matched by the same array element. So (to switch to shell syntax) to match all documents which have meta city Paris you would do
db.collection.find( {Meta:{$elemMatch:{Name:"City",Value:"Paris"}}} )
This assures you won't match something which has Name: "somethingelse", Value: "Paris" somewhere in its array with a different array element matching the Name:"City".
Now, default combination for combining query conditions is "and" so you can continue adding attributes:
db.collection.find( {Meta: {
$elemMatch:{Name:"City",Value:"Paris"},
$elemMatch:{Name:"State",Value:"France"}
}
}
)
Now if you want to add another condition you keep adding it but if you want a NOT then you do it like this:
db.collection.find( {Meta: {
$elemMatch:{Name:"City",Value:"Paris"},
$elemMatch:{Name:"State",Value:"France"},
$not: {$elemMatch:{Name:"Arrondissement",Value:"Louvre"}}
}
}
)
I might be answering my own question here, but I'm new to MongoDB, so while this appears to give me the results I'm after, it might not be the optimum approach.
var result = collection.Find(
Query.And(
Query.ElemMatch("Meta", Query.EQ("Name", "City")),
Query.ElemMatch("Meta", Query.EQ("Value", "Paris")),
Query.ElemMatch("Meta", Query.EQ("Name", "State")),
Query.ElemMatch("Meta", Query.EQ("Value", "France")))
);
Which leads to a follow up - how would I get all of the documents whose 'City' is 'Paris' and 'State' is 'France' but whose 'Arrondissement' is not 'Louvre'?