This is my collection
{
"_id" : '50001',
"data" :
[
{
"name" : "ram",
"grade" : 'A'
},
{
"name" : "jango",
"grade" : 'B'
},
{
"name" : "remo",
"grade" : 'A'
}
]
}
Here I want to update the object corresponds to "name": "jango" and have to create a new entry to the Array if "jango" is absent.
I can create a new entry but failed in "create or update".
I tried this way in mongo interpreter
db.MyCollection.update({'_id': '50001', "data.name" :"jango"}, {'$set':{'data': {'data.$.grade':'A'}}}, upsert=true)
but showing
not okForStorage
Mongo nested update so you should know the position or $ of update values below may help
db.collecionName.update(
{'_id': '50001', "data.name" :"jango"},
{'$set':{'data.1.grade':'A'}}, upsert=true)
or
db.collecionName.update(
{'_id': '50001', "data.name" :"jango"},
{'$set':{'data.$.grade':'A'}}, upsert=true)
You almost there:
db.YourCollection.update(
{ '_id':'50001', <-- to find document
'data.name': 'jango' < -- to find element of the array
},
{ '$set': { "data.$.grade" : 'A' } } <-- with .$ you reference array element from first argument
)
Link to documentation
Related
I have an entry stored on my collection like this:
{
"_id" : ObjectId("5d416c595f19962ff0680dbc"),
"data" : {
"a" : 6,
"b" : [
"5c35f04c4e92b8337885d9a6"
]
},
"image" : "123.jpg",
"hyperlinks" : "google.com",
"expirydate" : ISODate("2019-08-27T06:10:35.074Z"),
"createdate" : ISODate("2019-07-31T10:24:25.311Z"),
"lastmodified" : ISODate("2019-07-31T10:24:25.311Z"),
"__v" : 0
},
{
"_id" : ObjectId("5d416c595f19962ff0680dbd"),
"data" : {
"a" : 90,
"b" : [
"5c35f04c4e92b8337885d9a7"
]
},
"image" : "456.jpg",
"hyperlinks" : "google.com",
"expirydate" : ISODate("2019-08-27T06:10:35.074Z"),
"createdate" : ISODate("2019-07-31T10:24:25.311Z"),
"lastmodified" : ISODate("2019-07-31T10:24:25.311Z"),
"__v" : 0
}
I have to write the query for push userid on b array which is under data object and increment the a counter which is also under data object.
For that, I wrote the Code i.e
db.collection.updateOne({_id: ObjectId("5d416c595f19962ff0680dbd")},
{$inc: {'data.a': 1}, $push: {'data.b': '124sdff54f5s4fg5'}}
)
I also want to check that if that id exist on array then return the response that following id exist, so for that I wrote extra query which will check and if id exist then return the error response that following id exist,
My question is that any single query will do this? Like I don't want to write Two Queries for single task.
Any help is really appreciated for that
You can add one more check in the update query on "data.b". Following would be the query:
db.collection.updateOne(
{
_id: ObjectId("5d416c595f19962ff0680dbd"),
"data.b":{
$ne: "124sdff54f5s4fg5"
}
},
{
$inc: {'data.a': 1},
$push: {'data.b': '124sdff54f5s4fg5'}
}
)
For duplicate entry, you would get the following response:
{ "acknowledged" : true, "matchedCount" : 0, "modifiedCount" : 0 }
If matched count is 0, you can show the error that the id already exists.
You can use the operator $addToSet to check if the element already exits in the array.
db.collection.updateOne({_id: ObjectId("5d416c595f19962ff0680dbd")},
{$inc: {'data.a': 1}, $addToSet: {'data.b': '124sdff54f5s4fg5'}}
)
Here is my news document structure
{
"_id" : ObjectId("5bff0903bd9a221229c7c9b2"),
"title" : "Test Page",
"desc" : "efdfr",
"mediaset_list" : [
{
"_id" : ObjectId("5bfeff94bd9a221229c7c9ae"),
"medias" : [
{
"_id" : ObjectId("5bfeff83bd9a221229c7c9ac"),
"file_type" : "png",
"file" : "https://aws.com/gg.jpg",
"file_name" : "edf.jpg"
},
{
"_id" : ObjectId("5bfeff83bd9a221229c7c9ad"),
"file_type" : "mov",
"file" : "https://aws.com/gg.mov",
"file_name" : "abcd.mov"
}
]
}
]}
The queries that i've tried are given below
Approach 1
db.news.find_and_modify({},{'$pull': {"mediaset_list": {"medias": {"$elemMatch" : {"_id": ObjectId('5bfeff83bd9a221229c7c9ac')}} }}})
Approach 2
db.news.update({},{'$pull': {"mediaset_list.$.medias": {"_id": ObjectId('5bfeff83bd9a221229c7c9ac')}} })
Issue we are facing
The above queries are removing entire elements inside 'mediaset_list' . But i only want to remove the element inside 'medias' matching object ID.
Since you have two nested arrays you have to use arrayFilters to indicate which element of outer array should be modified, try:
db.news.update({ _id: ObjectId("5bff0903bd9a221229c7c9b2") },
{ $pull: { "mediaset_list.$[item].medias": { _id: ObjectId("5bfeff83bd9a221229c7c9ad") } } },
{ arrayFilters: [ { "item._id": ObjectId("5bfeff94bd9a221229c7c9ae") } ] })
So item is used here as a placeholder which will be used by MongoDB to determine which element of mediaset_list needs to be modified and the condition for this placeholder is defined inside arrayFilters. Then you can use $pull and specify another condition for inner array to determine which element should be removed.
From #micki's mongo shell query (Answer above) , This is the pymongo syntax which will update all news document with that media id .
db.news.update_many({},
{
"$pull":
{ "mediaset_list.$[item].medias": { "_id": ObjectId("5bfeff83bd9a221229c7c9ad") } } ,
},
array_filters=[{ "item._id": ObjectId("5bfeff94bd9a221229c7c9ae")}],
upsert=True)
Given a mongodb data of
{
"_id" : ObjectId("552f283dd951e49c6f2f451d"),
"uuid" : "1-2-1-b95a4040-e29d-11e4-bce8-0381ce4bc8a5",
"sub" : [
{
"prod" : 30,
"var" : 0,
"status" : "Test",
"files" : [
{
"filePath" : "20150415/2-1/21001429153881552f2859699769.82145796.jpg"
},
{
"filePath" : "20150415/2-1/21001429153880552f28589ca9a8.67013013.jpg"
}
]
},
{
"prod" : 10,
"var" : 0,
"status" : "Pending",
"files" : []
}
],
"process_marker" : 3
}
I would want to update the status of "sub.status" where "uuid" : "1-2-1-b95a4040-e29d-11e4-bce8-0381ce4bc8a5", "sub.prod":10, "sub.prod":0
Normally we'd use the "$" to modify the resulting index as seen below:
use targetDB
db.collection.update({
"uuid" : "1-2-1-b95a4040-e29d-11e4-bce8-0381ce4bc8a5",
"sub.prod":10,
"sub.var":0
},{
"$set":{"sub.$.status":"MyNewValue"}
})
==== BUT THE CODE ABOVE DOES NOT UPDATE THE CORRECT $ TARGET ====
It updates the "prod":30, "var":0 set... Why is that?
If we limit the query conditions for two key value pairs as seen below, the correct array set is updated
use targetDB
db.collection.update({
"uuid" : "1-2-1-b95a4040-e29d-11e4-bce8-0381ce4bc8a5",
"sub.prod":10
},{
"$set":{"sub.$.status":"MyNewValue"}
})
==== THE CODE ABOVE UPDATES THE CORRECT $ TARGET ====
I'm confused that a more detailed find query would result in updating the wrong array set. Is this a bug or did I do something wrong?
MongoDB version : 3.0.2
There is no bug in mongoDB, problem in your query is that you used first match "sub.prod":10 and then "sub.var":0 but in updated it takes latest value in your case "sub.var":0 takes and match first matching array where "sub.var":0 that why it updated only "prod" : 30 array element. More ref. click here.
In this case you should use mongo $elemMatch with $and conditions as below
db.collectionName.update({
"uuid": "1-2-1-b95a4040-e29d-11e4-bce8-0381ce4bc8a5",
"sub": {
"$elemMatch": {
"$and": [{
"prod": 10
}, {
"var": 0
}]
}
}
}, {
"$set": {
"sub.$.status": "MyNewValue"
}
})
Aggregate, $unwind and $group is not my solution as they make query very slow, there for I am looking to get my record by db.collection.find() method.
The problem is that I need more then one value from sub array. For example from the following example I want to get the "type" : "exam" and "type" : "quiz" elements.
{
"_id" : 22,
"scores" : [
{
"type" : "exam",
"score" : 75.04996547553947
},
{
"type" : "quiz",
"score" : 10.23046475899236
},
{
"type" : "homework",
"score" : 96.72520512117761
},
{
"type" : "homework",
"score" : 6.488940333376703
}
]
}
I am looking something like
db.students.find(
// Search criteria
{ '_id': 22 },
// Projection
{ _id: 1, scores: { $elemMatch: { type: 'exam', type: 'quiz' } }}
)
The result should be like
{ "_id": 22, "scores" : [ { "type" : "exam", "type" : "quiz" } ] }
But this over ride the type: 'exam' and returns only type: 'quiz'. Have anybody any idea how to do this with db.find()?
This is not possible directly using find and elemMatch because of following limitation of elemMatch and mongo array fields.
The $elemMatch operator limits the contents of an field from the query results to contain only the first element matching the $elemMatch condition. ref. from $elemMacth
and mongo array field limitations as below
Only one positional $ operator may appear in the projection document.
The query document should only contain a single condition on the array field being projected. Multiple conditions may override each other internally and lead to undefined behavior. ref from mongo array field limitations
So either you tried following this to find out only exam or quiz
db.collectionName.find({"_id":22,"scores":{"$elemMatch":{"type":"exam"}}},{"scores.$.type":1}).pretty()
is shows only exam scores array.
Otherwise you should go through aggregation
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.