I want to add a key inside mongodb add function. I am doing this right now.
$addToSet : {
"msges":{
time:{"from":uname,"title":title,"msg":msg,"read":false}
}
}
time is a variable that is coming from the paramater. It has time inside it as hh:mm:ss A. But when the query runs, instead of time as key, string "time" gets print as key. Any ideas what should I do?
Enclose your variable in [] :
$addToSet: {
"msges": {
[time]: { "from": uname, "title": title, "msg": msg, "read": false }
}
}
For instance :
var myfield = "custom_field";
db.test.update({
_id: 1
}, {
$addToSet: {
letters: [{
[myfield]: 1
}, {
[myfield]: 2
}]
}
})
It gives :
{ "_id" : 1, "letters" : [ [ { "custom_field" : 1 }, { "custom_field" : 2 } ] ] }
Related
I have a mongodb collection with a number of objects like this:
{
"_id" : "1234",
"type" : "automatic",
"subtypes" : [
{
"_id" : "dfgd",
"name" : "test subtype",
"subjetRequired" : true,
},
{
"_id" : "dfgd",
"name" : "test subtype2",
"subjetRequired" : false,
}
],
"anotherField" : "some value"
}
As you can see, one of the keys in the subtypes array is incorrectly spelled - "subjetRequired" instead of "subjectRequired".
I want to correct that key name. How can I do that.
I'll preface this by saying I've not worked with mongodb very much in the past.
After a lot of researching, the best I could come up with is the following (which doesn't work):
function remap(doc) {
subtypes = doc.subtypes;
var count = 0;
subtypes.forEach(function(subtype){
db.taskType.update({"_id": subtype._id}, {
$set: {"subtypes.subjectRequired" : subtype.subjetRequired},
$unset: {"subtypes.subjetRequired": 1}
});
}
)
}
db.taskType.find({"subtypes.subjetRequired":{$ne:null}}).forEach(remap);
This doesn't work.
I know the loop is correct, as if I replace the other logic with print statements I can access and print the fields who's names I want to modify.
What am I doing wrong here?
You can use this update and avoid using any code, it's also stable so you can execute it multiple times with no fear.
db.collection.updateMany({
"subtypes.subjetRequired": {
$exists: true
}
},
[
{
$set: {
subtypes: {
$map: {
input: "$subtypes",
in: {
$mergeObjects: [
"$$this",
{
subjectRequired: "$$this.subjetRequired",
}
]
}
}
}
}
},
{
$unset: "subtypes.subjetRequired"
}
])
Mongo Playground
I could modify your loop to override the whole array of subtypes:
function remap(doc) {
correctSubtypes = doc.subtypes.map(({ subjetRequired, ...rest }) => ({
...rest,
subjectRequired: subjetRequired,
}));
var count = 0;
db.taskType.findByIdAndUpdate(doc._id, {
$set: {
subtypes: correctSubtypes,
},
});
}
I have a collection in MongoDB in which one of the documents looks like this:
{
_id: ObjectId("6162883719592ea3350d3c87"),
fullName: 'Random User',
username: 'ruser1',
password: 'asdadasd',
portfolio: [ { equity: [] }, { crypto: [] }, { etf: [] }, { cash: [] } ]
}
I am trying to append a new object of the following format to the equity array inside the portfolio.
Object format:
{
name : "AAPL",
quantity : 1,
price : 100
}
I was trying to use the $push to do this operation, but I'm encountering the following error:
db.users.updateOne(
{_id : ObjectId("6162883719592ea3350d3c87")},
{$push : {"portfolio.equity" : {
name : "AAPL",
quantity : 1,
price : 100
}
}
}
)
MongoServerError: Cannot create field 'equity' in element {portfolio: [ { equity: [] }, { crypto: [] }, { etf: [] }, { cash: [] } ]}
I have also tried to use portfolio.$.equity, but that did not work either.
db.users.updateOne(
{_id : ObjectId("6162883719592ea3350d3c87")} ,
{$push : {"portfolio.$.equity" : {name : "AAPL", price : 100, quantity : 1}}}
)
MongoServerError: The positional operator did not find the match needed from the query.
In short, I am trying to append an object to an array inside an object's object.
How can I resolve this error or what is the appropriate way to do this?
You can use arrayFilters with check portfolio.equity field is existed via $exists.
db.users.updateOne({
_id: ObjectId("6162883719592ea3350d3c87")
},
{
$push: {
"portfolio.$[portfolio].equity": {
name: "AAPL",
price: 100,
quantity: 1
}
}
},
{
arrayFilters: [
{
"portfolio.equity": {
$exists: true
}
}
]
})
Sample Mongo Playground
On all documents of my collection I want to perform a $trim operation to a specific field of an object that is in an array.
Example:
{
"_id" : ObjectId("53857680f7b2eb611e843a32"),
"company": Testcompany
"customer" :
"name": Testuser,
"addresses" : [
{
"_id" : ObjectId("5d6d2f96e3fdc8001077ac6c"),
"street" : "Teststreet. ",
"houseNr" : "133",
},
{
"_id" : ObjectId("5d6d2f96e3fdc8001077ac7b"),
"street" : " Simplestreet. ",
"houseNr" : "12",
}
],
}
In the example, I want to $trim all values of the field: "customer.addresses.street"
To answer the upcoming questions:
I know the article you mentioned (Removing white spaces (leading and trailing) from string value) but theres no example how to do it within an array.
My problem is, how to access the attributes within an array, heres the example of plain values:
[{ $set: { category: { $trim: { input: "$category" } } } }],
Yes, I want to update the values of all documents within the collection
One possible way to do:
db.YOUR_COLLECTION.find({}).forEach(
function(doc) {
db.Trim.update(
{ "_id":doc._id },
{
"$set": {
"customer.addresses":doc.customer.addresses.map(
function(child) {
return Object.assign(
child,
{ street: child.street.trim() }
)
}
)
}
}
)
}
)
Obs: Solution with Javascript Executed in MongoShell.
You can use $map and $trim in an updateMany aggregation pipeline like this :
db.YOUR_COLLECTION.updateMany({"customer.addresses":{$ne:null}},[
{
$set: {
"customer.addresses":
{
$map: {
input: "$customer.addresses",
as: "address",
in: { $trim: { input: "$$address" } }
}
}
}
}
])
I have such a schema:
doc:
{
//Some fields
visits:
[
{
userID: Int32
time: Int64
}
]
}
I want to first check if a specific userID exists, if not, push a document with that userID and system time, else just update time value. I know neither $push nor $addToSet are not able to do that. Also using $ with upsert:true doesn't work, because of official documentation advice which says DB will use $ as field name instead of operator when trying to upsert.
Please guide me about this. Thanks
You can use $addToSet to add an item to the array and $set to update an existing item in this array.
The following will add a new item to the array if the userID is not found in the array :
db.doc.update({
visits: {
"$not": {
"$elemMatch": {
"userID": 4
}
}
}
}, {
$addToSet: {
visits: {
"userID": 4,
"time": 1482607614
}
}
}, { multi: true });
The following will update the subdocument array item if it matches the userId :
db.doc.update({ "visits.userID": 2 }, {
$set: {
"visits.$.time": 1482607614
}
}, { multi: true });
const p = await Transaction.findOneAndUpdate(
{
_id: data.id,
'products.id': { $nin: [product.id] },
},
{
$inc: {
actualCost: product.mrp,
},
$push: {
products: { id: product.id },
},
},
{ new: true }
);
or
db.collection.aggregate([
{
"$match": {
"_id": 1
}
},
{
"$match": {
"sizes.id": {
"$nin": [
7
]
}
}
},
{
"$set": {
"price": 20
}
}
])
https://mongoplayground.net/p/BguFa6E9Tra
I know it's very late. But it may help others. Starting from mongo4.4, we can use $function to use a custom function to implement our own logic. Also, we can use the bulk operation to achieve this output.
Assuming the existing data is as below
{
"_id" : ObjectId("62de4e31daa9b8acd56656ba"),
"entrance" : "Entrance1",
"visits" : [
{
"userId" : 1,
"time" : 1658736074
},
{
"userId" : 2,
"time" : 1658736671
}
]
}
Solution 1: using custom function
db.visitors.updateMany(
{_id: ObjectId('62de4e31daa9b8acd56656ba')},
[
{
$set: {
visits: {
$function: {
lang: "js",
args: ["$visits"],
body: function(visits) {
let v = []
let input = {userId: 3, time: Math.floor(Date.now() / 1000)};
if(Array.isArray(visits)) {
v = visits.filter(x => x.userId != input.userId)
}
v.push(input)
return v;
}
}
}
}
}
]
)
In NodeJS, the function body should be enclosed with ` character
...
lang: 'js',
args: ["$visits"],
body: `function(visits) {
let v = []
let input = {userId: 3, time: Math.floor(Date.now() / 1000)};
if(Array.isArray(visits)) {
v = visits.filter(x => x.userId != input.userId)
}
v.push(input)
return v;
}`
...
Solution 2: Using bulk operation:
Please note that the time here will be in the ISODate
var bulkOp = db.visitors.initializeOrderedBulkOp()
bulkOp.find({ _id: ObjectId('62de4e31daa9b8acd56656ba') }).updateOne({$pull: { visits: { userId: 2 }} });
bulkOp.find({ _id: ObjectId('62de4e31daa9b8acd56656ba') }).updateOne({$push: {visits: {userId: 2, time: new Date()}}})
bulkOp.execute()
Reference link
My function looks like below.
function (x)
{
var SO2Min = db.AirPollution.aggregate(
[
{
$match : {"SO2":{$ne:'NA'}, "State":{$eq: x} }
},
{
$group:
{
_id: x,
SO2MinQuantity: { $min: "$SO2" }
}
},
{
$project:
{SO2MinQuantity: '$SO2MinQuantity'
}
}
]
)
db.AirPollution.update
(
{
"State": "West Bengal"},
{
$set: {
"MaxSO2": SO2Max
}
},
{
"multi": true
}
);
}
Here, AirPolltuion is my Collection. If I run this function, the collection gets updated with new column MaxSO2 as below.
{
"_id" : ObjectId("5860a2237796484df5656e0c"),
"Stn Code" : 11,
"Sampling Date" : "02/01/15",
"State" : "West Bengal",
"City/Town/Village/Area" : "Howrah",
"Location of Monitoring Station" : "Bator, Howrah",
"Agency" : "West Bengal State Pollution Control Board",
"Type of Location" : "Residential, Rural and other Areas",
"SO2" : 10,
"NO2" : 40,
"RSPM/PM10" : 138,
"PM 2.5" : 83,
"MaxSO2" : {
"_batch" : [
{
"_id" : "West Bengal",
"SO2MaxQuantity" : 153
}
],
"_cursor" : {}
}
}
Where we can see, that MaxSO2 has been added as a sub document. But I want that column to be added inside same document as a field, not as a part of sub document. Precisely, I dont want batch and cursor fields to come up. Please help.
Since the aggregate function returns a cursor, you can use the toArray() method which returns an array that contains all the documents from a cursor and then access the aggregated field. Because you are returning a single value from the aggregate, there's no need to iterate the results array, just access the first and only single document in the result to get the value.
Once you get this value you can then update your collection using updateMany() method. So you can refactor your code to:
function updateMinAndMax(x) {
var results = db.AirPollution.aggregate([
{
"$match" : {
"SO2": { "$ne": 'NA' },
"State": { "$eq": x }
}
},
{
"$group": {
"_id": x,
"SO2MinQuantity": { "$min": "$SO2" },
"SO2MaxQuantity": { "$max": "$SO2" }
}
},
]).toArray();
var SO2Min = results[0]["SO2MinQuantity"];
var SO2Max = results[0]["SO2MaxQuantity"];
db.AirPollution.updateMany(
{ "State": x },
{ "$set": { "SO2MinQuantity": SO2Min, "SO2MaxQuantity": SO2Max } },
);
}
updateMinAndMax("West Bengal");