{Crs:{[
{Cr: {
"_id" : ObjectId("5a75baada0f20bd4e612d480"),
"Number" : 400,
"Page" : 24,
"DC" : "NE",
}},
{Cr: {
"_id" : ObjectId("5a75baada0f20bd4e612d489"),
"Number" : 300,
"Page" : 14,
"DC" : "100",
}},
]}}
I have this data that i model using aggregate and I would like to know how can i remove "DC" field from all elements of the array using aggregate.
>db.crs.aggregate(
[
{$group : {_id : null, crs : {$push : {cr : "$$ROOT"}}}},
{$project : {_id : 0}}
]
)
This is what did to model that data.
I think its something related with $project.
First of all, your document is not a valid JSON schema. You might reconsider the following schema for that particular document.
{
Crs:[
{
"_id" : ObjectId("5a75baada0f20bd4e612d480"),
"Number" : 400,
"Page" : 24,
"DC" : "NE"
},
{
"_id" : ObjectId("5a75baada0f20bd4e612d489"),
"Number" : 300,
"Page" : 14,
"DC" : "100"
}
]
}
Having above schema, you can easily remove DC field using $unset aggregate operator.
db.crs.aggregate([{$unset: 'Crs.DC'}]);
Related
I have a data collection which contains a set of records in the following format.
{
"_id" : 22,
"title" : "3D User Interfaces with Java 3D",
"isbn" : "1884777902",
"pageCount" : 520,
"publishedDate" : ISODate("2000-08-01T07:00:00Z"),
"thumbnailUrl" : "https://s3.amazonaws.com/AKIAJC5RLADLUMVRPFDQ.book-thumb-images/barrilleaux.jpg",
"longDescription" : "Description",
"status" : "PUBLISH",
"authors" : [
"Jon Barrilleaux"
],
"categories" : [
"Java",
"Computer Graphics"
]
},
{
"_id" : 23,
"title" : "Specification by Example",
"isbn" : "1617290084",
"pageCount" : 0,
"publishedDate" : ISODate("2011-06-03T07:00:00Z"),
"thumbnailUrl" : "https://s3.amazonaws.com/AKIAJC5RLADLUMVRPFDQ.book-thumb-images/adzic.jpg",
"status" : "PUBLISH",
"authors" : [
"Gojko Adzic"
],
"categories" : [
"Software Engineering"
]
}
Please note that the 'categories' is an array.
I want to count the published books for each category. I tried the following solution, but it treated the entire array as one group.
db.books.aggregate([
{
$group:{_id:"$categories", total:{$sum:1}}
}
])
Instead of so, I want to count the number of records for each individual category value inside 'categories' array.
You should first use $unwind which outputs one document for each element in the array.
db.books.aggregate([
{
$unwind : "$categories"
},
{
$group : { _id : "$categories", total: { $sum: 1 } }
}
])
Lets say here is the same document:
{
"_id" : 1.0,
"custname" : "metlife",
"address" : {
"city" : "Bangalore",
"country" : "INDIA"
}
}
And if I want to push an extra field to this document, something like below:
db.customers.updateMany(
{"address.country":"INDIA"},
{$push : {city: "$address.country"}}
)
It results in wrong update:
{
"_id" : 1.0,
"custname" : "metlife",
"address" : {
"city" : "Bangalore",
"country" : "INDIA"
},
"city" : "$address.city"
}
Instead of this:
{
"_id" : 1.0,
"custname" : "metlife",
"address" : {
"city" : "Bangalore",
"country" : "INDIA"
},
"city" : "Bangalore"
}
How do I achieve the above result?
You can't refer to other field values in update currently (more here). There is a workaround in aggregation framework (using $out) but it will replace entire collection.
I think that you can consider using $rename in your case. It will not add new field but it can move city to the top level of your document.
db.customers.updateMany({"address.country":"INDIA"}, {$rename: {"address.city": "city"}})
will give you following structure:
{ "_id" : 1, "custname" : "metlife", "address" : { "country" : "INDIA" }, "city" : "Bangalore" }
like #mickl said : You can't refer to other field values in update currently,
you have to iterate through your collection to update the documents, try this :
db.eval(function() {
db.collection.find({"address.country":"INDIA"}).forEach(function(e) {
e.city= e.address.city;
db.collection.save(e);
});
});
Keep in mind that this will block the DB until all updates are done.
try this
db.customers.updateMany(
{"address.country":"INDIA"},
{$push : {city: "address.country"}}
)
remove $ sign
I have this data that i moddeling after i imported a csv file:
{Main: {
"Name" : "MainNAme1",
"age" : "age1",
"ge" :"ge1",
{Crs:{[
{Cr: {
"_id" : ObjectId("5a75baada0f20bd4e612d480"),
"Number" : 400,
"Page" : 24,
"DC" : "NE",
}},
{Cr: {
"_id" : ObjectId("5a75baada0f20bd4e612d489"),
"Number" : 300,
"Page" : 14,
"DC" : "100",
}},
]}},
}}
And i would like to know how can i create an new array inside a root element like this:
{Main: {
"Name" : "MainNAme1",
"info":[{
"age" : "age1",
"ge" :"ge1",
}],
{Crs:{[
{Cr: {
"_id" : ObjectId("5a75baada0f20bd4e612d480"),
"Number" : 400,
"Page" : 24,
"DC" : "NE",
}},
{Cr: {
"_id" : ObjectId("5a75baada0f20bd4e612d489"),
"Number" : 300,
"Page" : 14,
"DC" : "100",
}},
]}},
}}
I'm using aggregate to moddeling this.
Going off your OP. You are looking to move age and ge into its own array. You could use $addToSet during your $group stage
Try adding this into your $group pipline:
"Info" : { $addToSet : { "age": "$age", "ge" : "$ge" } } }}
output
"Info" : [
{
"age" : "age1",
"ge" : "ge1"
}]
You're looking for the $addFields stage which is available from MongoDB v3.4 onwards. Before that you'd need to use $project.
db.collection.aggregate({
$addFields: {
"info": [{
"age": "$Main.age",
"ge": "$Main.ge"
}]
}
})
Below is my code returned after the commant db.slist.findOne()
How do I add an id to the array with "iname" as "Soap"?
I need to write a query that seaches the all the "itemlist"array in the collection and if the any document inside an embedded document have "iname" as "Soap", a new row should be inserted above "iname:"Soap" as "itemID" and set an item ID myself. Can someone help me find the correct query for it?
Also this seems like a hard question, please let me know if you are finding hard to understand the question.
{
"_id" : ObjectId("5914213e9f75f9119575c1d7"),
"name" : "Athif",
"age" : 23,
"address" : {
"house" : "675/38B",
"street" : "West Hill",
"city" : "Chungam",
"pincode" : 676507
},
"itemlist" : [
{
"iname" : "Soap",
"quantity" : 2,
"price" : 10,
"rate" : 20
},
{
"iname" : "helmet",
"quantity" : 1,
"price" : 500,
"rate" : 500
},
{
"iname" : "Table",
"quantity" : 2,
"price" : 5000,
"rate" : 10000
}
]
}
For updating array elements mongodb provides positional operator $. when you apply query to find any array elements the positional operator $ holds the position of that embedded document that can be modified in update operation. So, here you go!( suppose your collection name is demo)
db.demo.update({ "itemlist.iname":"Soap" }, { $set:{"itemlist.$.itemID":"your_id"}})
Mongoose/Mongo noob here:
My Data
Here is my simplified data, each user has his own document
{ "__v" : 1,
"_id" : ObjectId( "53440e94c02b3cae81eb0065" ),
"email" : "test#test.com",
"firstName" : "testFirstName",
"inventories" : [
{ "_id" : "active",
"tags" : [
"inventory",
"active",
"vehicles" ],
"title" : "activeInventory",
"vehicles" : [
{ "_id" : ObjectId( "53440e94c02b3cae81eb0069" ),
"tags" : [
"vehicle" ],
"details" : [
{ "_id" : ObjectId( "53440e94c02b3cae81eb0066" ),
"year" : 2007,
"transmission" : "Manual",
"price" : 1000,
"model" : "Firecar",
"mileageReading" : 50000,
"make" : "Bentley",
"interiorColor" : "blue",
"history" : "CarProof",
"exteriorColor" : "blue",
"driveTrain" : "SWD",
"description" : "test vehicle",
"cylinders" : 4,
"mileageType" : "kms" } ] } ] },
{ "title" : "soldInventory",
"_id" : "sold",
"vehicles" : [],
"tags" : [
"inventory",
"sold",
"vehicles" ] },
{ "title" : "deletedInventory",
"_id" : "deleted",
"vehicles" : [],
"tags" : [
"inventory",
"sold",
"vehicles" ] } ] }
As you can see, each user has an inventories property that is an array that contains 3 inventories (activeInventory, soldInventory and deletedInventory)
My Query
Given an user's email a a vehicle ID, i would like my query to go through find the user's activeInventory and return just the vehicle that matches the ID. Here is what I have so far:
user = api.mongodb.userModel;
ObjectId = require('mongoose').Types.ObjectId;
return user
.findOne({email : params.username})
.select('inventories')
.find({'title': 'activeInventory'})
//also tried
//.where('title')
//.equals('activeInventory')
.exec(function(err, result){
console.log(err);
console.log(result);
});
With this, result comes out as an empty array. I've also tried .find('inventories.title': 'activeInventory') which strangely returns the entire inventories array. If possible, I'd like to keep the chaining query format as I find it much more readable.
My Ideal Query
return user
.findOne({email : params.username})
.select('inventories')
.where('title')
.equals('activeInventory')
.select('vehicles')
.id(vehicleID)
.exec(cb)
Obviously it does not work but it can give you an idea what I'm trying to do.
Using the $ positional operator, you can get the results. However, if you have multiple elements in the vehicles array all of them will be returned in the result, as you can only use one positional operator in the projection and you are working with 2 arrays (one inside another).
I would suggest you take a look at the aggregation framework, as you'll get a lot more flexibility. Here's an example query for your question that runs in the shell. I'm not familiar with mongoose, but I guess this will still help you and you'd be able to translate it:
db.collection.aggregate([
// Get only the documents where "email" equals "test#test.com" -- REPLACE with params.username
{"$match" : {email : "test#test.com"}},
// Unwind the "inventories" array
{"$unwind" : "$inventories"},
// Get only elements where "inventories.title" equals "activeInventory"
{"$match" : {"inventories.title":"activeInventory"}},
// Unwind the "vehicles" array
{"$unwind" : "$inventories.vehicles"},
// Filter by vehicle ID -- REPLACE with vehicleID
{"$match" : {"inventories.vehicles._id":ObjectId("53440e94c02b3cae81eb0069")}},
// Tidy up the output
{"$project" : {_id:0, vehicle:"$inventories.vehicles"}}
])
This is the output you'll get:
{
"result" : [
{
"vehicle" : {
"_id" : ObjectId("53440e94c02b3cae81eb0069"),
"tags" : [
"vehicle"
],
"details" : [
{
"_id" : ObjectId("53440e94c02b3cae81eb0066"),
"year" : 2007,
"transmission" : "Manual",
"price" : 1000,
"model" : "Firecar",
"mileageReading" : 50000,
"make" : "Bentley",
"interiorColor" : "blue",
"history" : "CarProof",
"exteriorColor" : "blue",
"driveTrain" : "SWD",
"description" : "test vehicle",
"cylinders" : 4,
"mileageType" : "kms"
}
]
}
}
],
"ok" : 1
}
getting the chaining query format ... i dont know how to parse it but, what you are searching for is projection, you should take a look to http://docs.mongodb.org/manual/reference/operator/projection/
it would probably look like this :
user.findOne({email: params.username}, {'inventories.title': {$elemMatch: "activeInventory", 'invertories.vehicle.id': $elemMatch: params.vehicleId}, function(err, result) {
console.log(err);
console.log(result);
})