{
"_id":"12345",
"model":{
"T":0,
"serviceTask":[
{
"_id":"6789",
"obj":{
"params" :{
"action": "getEmployeeData",
"employeeId":"123"
},
"url":"www.test.com",
"var":"test",
},
"opp":100
}
]
}
}
I have similar structured documents in my collection. How do I query the documents that match action value to "getEmployeeData". I tried dot notation with $elemMatchbut couldn't get the results.
Dot notation works fine here, it will return the document if serviceTask contains at least one action set to getEmployeeData
db.collection.find({
"model.serviceTask.obj.params.action": "getEmployeeData"
})
Related
I have multiple documents(3 documents in this example) in one collection that looks like this:
{
_id:123,
bizs:[{_id:'',name:'a'},{_id:'',name:'b'}]
},
{
_id:456,
bizs:[{_id:'',name:'e'},{_id:'',name:'f'}]
}
{
_id:789,
bizs:[{_id:'',name:'x'},{_id:'',name:'y'}]
}
Now, I want to update the bizs subdocument by matching with my array of ids.
That is to say, my array filter for update query is [123,789], which will match against the _id fields of each document.
I have tried using findByIdAndUpdate() but that doesn't allow an array for the update query
How can I update the 2 matching documents (like my example above) without having to put findByIdAndUpdate inside a forloop to match the array element with the _id?
You can not use findByIdAndUpdate when updating multiple documents, findByIdAndUpdate is from mongoose which is a wrapper to native MongoDB's findOneAndUpdate. When you pass a single string as a filter to findByIdAndUpdate like : Collection.findByIdAndUpdate({'5e179dac627ef7823643cd97'}, {}) - then mongoose will internally convert string to ObjectId() & form it as a filter like :_id : ObjectId('5e179dac627ef7823643cd97') to execute findOneAndUpdate. So it means you can only update one document at a time, So if you've multiple documents to be updated use update with option {multi : true} or updateMany.
Assume if you wanted to push a new object to bizs, this is how query looks like :
collection.updateMany({ _id: { $in: [123, 456] } }, {
$push: {
bizs: {
"_id": "",
"name": "new"
}
}
})
Note : Update operations doesn't return the documents in response rather they will return write result which has information about n docs matched & n docs modified.
I am trying to update items in an array with unique ObjectIds (meaning add an object ID to array object that are missing them)
If I have an array of shirt objects in my collection and I try this:
db.people.update({
$and : [
_id: ObjectId('5eeb44c6a042791d28a8641f'),
{
$or: [
{ 'shirts._id': { $eq:null } },
{ 'shirts._id':{ $exists:false } }
]
}
]
},{
$set: { 'shirts.$[]._id': new ObjectId() }
},{
"multi" : true
}
);
It generates IDENTICAL ObjectsIDs for each array element, I would put an unique index on this however, the use case probably wont see more then 2-3 items in the array with edge cases hitting 5-6, which seems like an abuse of an index
How can I update multiple records or multiple array objects with a unique ObjectId?
When you use $set you're telling mongo to set that value to all matching elements. If the elements in the array are already defined as schemas, mongo will issue new ObjectIds for each one of them automatically.
Alternatively, you can use forEach and iterate over each matching element creating a new ObjectId.
Say you have an document saved like this:
{
_id: "1",
thingy: {
moreStuff: [
{
_id:"a",
moreComplicated: [
{
_id:"a1",
info: "test"
},
... // More similar elements
]
},
... // More similar elements
]
}
}
Suppose you already have a way to get the query of the document:
db.getCollection("thingies").find({"_id": 1});
Now you're looking for a way to update the "info" section inside the "a1" object nested within all those other objects and arrays. The only catch to this is that "moreStuff" and "moreComplicated" arrays are being updated constantly, so aiming by array location (like thingy.morestuff.0.moreComplicated.0.info) won't work. The only way to do it is by looking up the unique mongoID of each object.
How would you query the arrays by matching an element to value instead of an index? Bonus points if you can have a "find" query return a similar object.
I have some data structured like this in a mongo collection:
{ "list" : [ { "update_time" : NumberLong(1426690563), "provider" : NumberLong(4) } ] }
What I would like to do is query for all of the entries where the list includes a provider value of 4.
If it helps, all of the list arrays contain only one element.
What I am trying right now is this:
db.collection.find(
{
list: {
provider: 4
}
}
)
This does not work though, and always returns an empty set
Use the dot notation i.e. concatenate the name of the field that contains the array, with a dot (.) and the name of the field in the embedded document and use that as your query:
db.collection.find({"list.provider": 4})
You can also use the $elemMatch operator to specify multiple criteria on an array of embedded documents such that at least one embedded document satisfies all the specified criteria:
db.collection.find({
list: {
$elemMatch: {
provider: 4
}
}
})
I have a field in a MongoDB Collection like:
{
place = ['London','Paris','New York']
}
I need a query that will return only that particular entry of the array, where a specific character occurs. For Example, I want to search for the terms having the letter 'o'(case-insensitive) in them. It should just return 'London' and 'New York'.
I tried db.cities.find({"place":/o/i}), but it returns the whole array.
You'll need to $unwind using an aggregate query, then match.
db.cities.aggregate([ { $unwind:'$place' }, { $match: { place : {$regex: /o/i } } } ])
In simple you find with $regex below query will work without aggregation
db.collectionName.find({ place : {$regex: /o/i } })