We have Array of Object:
data = [
{
"_id": "629dc6282f912621c6e092d0",
"adsId": 1223,
"targetUrl": "http://www.yahoo.com",
"targetCapture": "1223-1654865246611.png",
"mediaFile": "1223-1654865245223"
},
{
"_id": "629dcf1497a5ba34d0d1e9a4",
"adsId": 1224,
"targetUrl": "http://www.yahoo.com",
"targetCapture": "1224-1654865246373.png",
"mediaFile": "1224-1654865245226"
}
]
I want to update conditional document of collection for each json object of data (Array of Object) without using the loop.
Is it possible in mongoDB to do the same or there is any other solution to do it.
Related
Im trying to filter the elements of this JSON array to return only the first element it will find.
{
"elements": [{
"urn": "urn:li:lyndaCourse:189800",
"details": {
"classifications": [{
"associatedClassification": {
"urn": "urn:li:lyndaCategory:9331",
"type": "LIBRARY"
}
},
{
"associatedClassification": {
"urn": "urn:li:lyndaCategory:8982",
"type": "SUBJECT"
}
},
{
"associatedClassification": {
"urn": "urn:li:lyndaCategory:8920",
"type": "LIBRARY"
}
}
]
}
}]
}
But this results in an EMPTY array [].
I tried this JSONPATH query in https://jsonpath.herokuapp.com/
$.elements[0].details.classifications..associatedClassification[?(#.type=='LIBRARY')][0]
Expecting to get:
[{
"urn": "urn:li:lyndaCategory:9331",
"type": "LIBRARY"
}]
Another way to filter the information is by filtering the property "classification" (without using ".."), and use "associatedClassification.type" in your filter, so you should have something like this:
$.elements[0].details.classifications[?(#.associatedClassification.type=='LIBRARY')]
With the above JSONPATH you will have all items which type is "LIBRARY" (in your example will return 2 items).
You mentioned you need only the first one of the filtered items, as far as I investigated it seems there's no posible solution to return only the first item using only JSONPATH (see the thread bellow):
https://github.com/json-path/JsonPath/issues/272
The following works on all elements:
$..classifications[?(#.associatedClassification.type=='LIBRARY')]
and returns a list of all matching associatedClassification objects.
JSONPath is expected to point inside the original document. Therefore, getting the first element from the result list would require post-processing, e.g. a separate JSONPath, e.g.
$.[0]
I have schemas each containing an array of objects looking like this:
{name: String, _id: ObjectId}
Each schemas array has multiple items, I need to match the penultimate (next to last) items _id inside an aggregate function, which currently looks like this:
{ "$match": {$expr: {$gt: [{"$arrayElemAt": ["$path._id", -2]}, mongoose.Types.ObjectId(req.params.id)]}}},
{ "$project": {
"_id": 1,
"name": 1,
"isFile": {
"$cond": [{"$eq": [{"$ifNull":["$data", null]}, null]},false, true]
}
}
}
(the current match function is my attempt, however it does not work)
Any help would be greatly appreciated!
Answer: use $eq instead of $gt...
I am trying to delete all documents from an array of documents that match this value but cannot figure it out,
This is my delete query that is not working, courses is the array I need to be in and code is the document I need to check to see its value for deletetion. So if courses.code == 123, then delete and keep going sort of thing.
result = await mongoClient.db(DB_NAME).collection("technologies").deleteMany({ 'courses': {$in: 'courses.code'} });
That is what it looks like in my collection.
"name": "Sass",
"description": "Sass (Syntactically awesome style sheets) is a preprocessor scripting language that is interpreted or compiled into Cascading Style Sheets (CSS).",
"difficulty":2,
"courses":[
{"code":"PROG2700","name":"Client Side Programming"},
{"code":"PROG3017","name":"Full Stack Programming"}
]
},
Any help would be great, thanks!
You can filter documents that contain the field you want to update
Do tests before updates on the original collection.
After some searches, I've found this method:
const filter = { }
db.collection.update(filter,
{
$pull: {
"courses": {
code: {
$in: [
"PROG3017",
"PROG2700"
]
}
}
}
},
{
multi: true
})
This pulls out any element in the array where the value of code is $in the array.
I have an object which is given back through my REST API and I need to iterate through it for synchronizing a DB. So the object contains another object called tables. The tables object has different arrays with table names and their key value pairs.
I could not loop through the tables object about two days whatever I did and it is really annoying getting null or undefined values back.
For example I tried iterating through the table array with the JavaScript function object.forEach((article)=>console.log(article.id,article.name));
const obj = response.content.tables.article;
function findArticles(obj) {
obj.forEach((article)=>console.log(article.id,article.name));
}
I can't get any value back. When I try to console.log(response.content); it shows me everything. As soon as I try to output response.content.tables it says undefined.
This is the structure of the object response.content:
{
"status": "1",
"message": "sync out request successfull",
"tables": {
"article": [
{
"id": 1,
"name": "baseball"
},
{
"id": 2,
"name": "truck"
},
],
"food": [],
"animals: []
}
}
Try converting the response to an object using JSON.parse(xyz) before attempting to get the properties.
var xyz = '{ "status": "1", "message": "sync out request successfull", "tables": { "article": [{"id": 1,"name": "baseball"},{"id": 2,"name": "truck"}],"food": [],"animals": []}}'
var obj = JSON.parse(xyz);
$(obj.tables).each(function (ix, el) {
console.log(el)
});
I solved it like this:
var obj = response.content;
var JSON = JSON.parse(obj);
var articleTable = JSON.tables.article;
articleTable.forEach((article)=>console.log(article.id,article.name));
After I parsed the response.content object to JSON it was available to access the nested objects as 'tables' and 'article'. After passing the article object with the articleTable variable to the forEach it has been possible to access each elements. Now I get results.
I really appreciate your help
T3.0 it wasn't able to solve the problem without you.
I am trying to initialize an observable array from a json object which is rendered from the server as Javascript/Json;
Basically I have a simple model (from the server) that looks like this
var BaseModel = { "changeRequestLocations":
[{ "location": "New Zealand", "devices":
[
{ "id": "5", "deviceName": "Server 1" },
{ "id": "6", "deviceName": "Server 2" }
],
"id": 1 }] };
I then initialize an observable array from the baseModel
this.changeRequestLocations = ko.observableArray(BaseModel.changeRequestLocations);
This basically does what I want but the "devices" element is an array not an observable array.
I really need to have it as an observable array - is there a way to tell Knockout to do this automatically or do I need to do it manually?
See a fiddle here that shows the case
In itself Knockout does not do this for you automatically, so
you do it manually like your jsfiddle
you use the Knockout.Mapping plugin which is designed for this scenario: convert plain JavaScript objects to objects with observable properties.
So in your example you just need to write:
this.changeRequestLocations = ko.mapping.fromJS(BaseModel.changeRequestLocations);
and the mapping plugin will convert your location array into an observable array.
Demo JSFiddle.