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MongoDB document update array element using findOneAndUpdate method in Java

Can someone look at this issue as we are not able to insert the array in the field 'd' as shown in the image below:
[![JSON Structure in MongoDB][1]][1]
{
"id": 12,
"articles": "art",
"author": "author"
}

You have to use arrayFilters to update a specific array element (with a condition). The array filters in Java is defined with FindOneAndUpdateOptions object.
List<Bson> arrFilters = new ArrayList<>();
arrFilters.add(new Document("elem.apn", "abcdef")); // this specifies the element search criteria
FindOneAndUpdateOptions updateOptions = new FindOneAndUpdateOptions().arrayFilters(arrFilters);
String [] dArray = { "app", "ban", "ora" }; // the "d" array to be added
Bson update = set("session.ps.$[elem].d", Arrays.asList(dArray));
String idStr = "5e37dc262f5ff4dfc935eb6b";
Bson queryFilter = eq("_id", new ObjectId(idStr));
Document result = coll.findOneAndUpdate(queryFilter, update, updateOptions);
System.out.println(result);
The same update operation in Mongo Shell:
var dArray = [ "app", "ban" ];
db.test.updateOne(
{ _id: ObjectId("5e37dc262f5ff4dfc935eb6b") },
{ $set: { "session.ps.$[elem].d" : dArray } },
{
arrayFilters: [ { "elem.apn": "abcdef" } ]
}
)
[EDIT ADD]
Updating the apn simultaneously with a new value "newVal" and adding a new string element "gua" to the d array (this will add a new array if the array doesn't exist):
db.test.updateOne(
{ _id: ObjectId("5e37dc262f5ff4dfc935eb6b") },
{
$set: { "session.ps.$[elem].apn": "newVal" }
$push: { "session.ps.$[elem].d" : "gua" }
},
{
arrayFilters: [ { "elem.apn": "abcdef" } ]
}
)
The Java code for the above Mongo Shell code:
List<Bson> arrayFilters = new ArrayList<>();
arrayFilters.add(new Document("elem.apn", "abcdef"));
FindOneAndUpdateOptions updateOptions =
new FindOneAndUpdateOptions().arrayFilters(arrayFilters);
Bson pushUpdate = push("session.ps.$[elem].d", "gua");
Bson setUpdate = set("session.ps.$[elem].apn", "newValue");
Bson update = combine(pushUpdate, setUpdate);
String idStr = "5e37dc262f5ff4dfc935eb6b";
Bson queryFilter = eq("_id", new ObjectId(idStr));
Document result = coll.findOneAndUpdate(queryFilter, update, updateOptions);

How do I group the results of mongodb query and implement in Java?

I have a collection in a Mongo database that looks like this:
{
"_id" : ObjectId("561b42d4e4b0d4227d011d2c"),
"product_related_data" : {
"depth" : 6,
"height" : 23,
"product_barcode" : "54491472",
"product_name" : "xyz product",
"product_uuid" : "009b9846-b3ad-49f7-a7a0-d35a04f83480",
"width" : 6
},
"sensostrip_data" : {
"barcode" : "130150208299",
"battery_level" : 2.894
},
"stock_related_data" : {
"calculated_max_product_percentage" : 15.625,
"calculated_min_product_percentage" : 12.5,
"current_stock" : 2,
"max_stock" : 6,
"stock_difference_percentage" : 0,
"stock_difference_value" : 0,
"stock_percentage" : 37.5
},
"store_data" : {
"city_uuid" : "cbb4dfe8-172b-11e4-a1f0-00163ed23ec2",
"ip" : "10.0.1.1",
"retailer_uuid" : "8c33c32c-5903-11e4-a1f0-00163ed23ec2",
"store_name" : "xyz store",
"store_uuid" : "15a6cc90-081f-11e5-b213-001e6745ff8d"
},
"time" : {
"check_date" : "2015-10-11 11:53:55",
"previous_check_date" : "2015-10-11 11:48:57"
},
"id" : "6be54bef-0aa3-456c-b912-1731f8154e7d"
}
The mongo query I'm currently executing returns all the documents for a list of store_uuid's and for a product_uuid, and looks like this:
db.readings
.find({ $and:[ {"store_data.store_uuid": {$in:["15a6cc90-081f-11e5-b213-001e6745ff8d","217b983b-5904-11e4-a1f0-00163ed23ec2","5337d78d-5904-11e4-a1f0-00163ed23ec2"]}}
,{"product_related_data.product_uuid": "f44aa29d-09ce-4902-bf12-d45d44b3dfd0"}]})
My current Java implementation (where I make use of projection) looks like this:
DBCollection table = databaseConncetion().getCollection("readings");
BasicDBObject sensorReturn = new BasicDBObject("sensostrip_data.barcode",1);
BasicDBObject clause1 = new BasicDBObject("store_data.store_uuid", new BasicDBObject("$in", StoreIds));
BasicDBObject clause2 = new BasicDBObject("product_related_data.product_uuid", productId);
BasicDBList and = new BasicDBList();
and.add(clause1);
and.add(clause2);
DBObject query = new BasicDBObject("$and", and);
DBCursor cursor = table.find(query, sensorReturn
.append("stock_related_data.stock_percentage",1)
.append("store_data.store_uuid",1)
.append("time.check_date", 1))
.sort(new BasicDBObject("time.check_date", -1))
.limit(100);
However I need this query to group the results for the latest check_date by barcode

The aggregation framework is at your disposal. Running the following aggregation pipeline will give you the desired result:
Mongo shell:
pipeline = [
{
"$match": {
"store_data.store_uuid": {
"$in": [
"15a6cc90-081f-11e5-b213-001e6745ff8d",
"217b983b-5904-11e4-a1f0-00163ed23ec2",
"5337d78d-5904-11e4-a1f0-00163ed23ec2"
]
},
"product_related_data.product_uuid": "f44aa29d-09ce-4902-bf12-d45d44b3dfd0"
}
},
{ "$sort": { "time.check_date": -1 } },
{
"$group": {
"_id": "$sensostrip_data.barcode",
"stock_percentage": { "$first": "$stock_related_data.stock_percentage" },
"store_uuid": { "$first": "$store_data.store_uuid" },
"check_date": { "$first": "$time.check_date" }
}
},
{ "$limit": 100 }
];
db.readings.aggregate(pipeline);
Java test implementation
public class JavaAggregation {
public static void main(String args[]) throws UnknownHostException {
MongoClient mongo = new MongoClient();
DB db = mongo.getDB("test");
DBCollection coll = db.getCollection("readings");
// create the pipeline operations, first with the $match
DBObject match = new BasicDBObject("$match",
new BasicDBObject("store_data.store_uuid", new BasicDBObject("$in", StoreIds))
.append("product_related_data.product_uuid", productId)
);
// sort pipeline
DBObject sort = new BasicDBObject("$sort",
new BasicDBObject("time.check_date", -1)
);
// build the $group operations
DBObject groupFields = new BasicDBObject( "_id", "$sensostrip_data.barcode"); // group by barcode
groupFields.put("stock_percentage", new BasicDBObject( "$first", "$stock_related_data.stock_percentage")); // get the first when ordered documents are grouped
groupFields.put("store_uuid", new BasicDBObject( "$first", "$store_data.store_uuid"));
groupFields.put("check_date", new BasicDBObject( "$first", "$time.check_date"));
// append any other necessary fields
DBObject group = new BasicDBObject("$group", groupFields);
// limit step
DBObject limit = new BasicDBObject("$limit", 100);
// put all together
List<DBObject> pipeline = Arrays.asList(match, sort, group, limit);
AggregationOutput output = coll.aggregate(pipeline);
for (DBObject result : output.results()) {
System.out.println(result);
}
}
}

Return nested elements in Json that equal search string - mongodb

I has the following json document in Mongo db. The show element will have several season elements which will also have several episodes elements that in turn have multiple questionEntry elements.
I want to return multiple questionElements where the questionElements metaTag entry equals my search. E.G. if a metaTag element equals my string the return it's parent questionEntry element and search across all elements nested in show.
{
"show":[
{
"season":[
{
"episodes":[
{
"questionEntry":{
"id":1,
"info":{
"seasonNumber":1,
"episodeNumber":5,
"episodeName":"A Hero Sits Next Door"
},
"questionItem":{
"theQuestion":"What is the name of the ringer hired by Mr. Weed?",
"attachedElement":{
"type":1,
"value":""
}
},
"options":[
{
"type":1,
"value":"Johnson"
},
{
"type":1,
"value":"Hideo"
},
{
"type":1,
"value":"Guillermo"
}
],
"answer":{
"questionId":1,
"answer":3
},
"metaTags":[
"Season 1",
"Episode 5",
"Trivia",
"Arya Stark",
"House Stark"
]
}
}
]
}
]
}
]
}
I'm usingthe latest Java Mongo driver in Windows 8.1 and using Mongodb 2.4.4. So my question is what is the best method to return a single or multiple qestionEntry element(s) over this entire show collection that match my search string?
Hopefully somebody here can help me with this.
EDIT:
private DB mongoDatabase;
private DBCollection mongoColl;
private DBObject dbObject;
// Singleton class
// Create client (server address(host,port), credential, options)
mongoClient = new MongoClient(new ServerAddress(host, port),
Collections.singletonList(credential),
options);
mongoDatabase = ClientSingleton.getInstance().getClient().getDB("MyDB");

Please try the below :
db.exp.aggregate([{"$redact":{"$cond": { if: {$gt:[ {"$size": {
$setIntersection : [ { "$ifNull": [ "$metaTags", []]},
["House Stark"]]} } , 0 ]} , then:"$$PRUNE",
else:"$$DESCEND" }}}]).pretty();
[OR]
EDIT :
db.exp.aggregate([{"$unwind":"$show"},
{"$unwind":"$show.season"},
{"$unwind":"$show.season.episodes"},
{"$match" : {"show.season.episodes.questionEntry.metaTags":{"$in":
["Trivia"]}}},
{"$group":{"_id":"$_id","episodes":{"$push":"$show.season.episodes"}
]);
JAVA CODE :
MongoClient client = new MongoClient();
List<String> continentList = Arrays.asList(new String[]{"Trivia"});
DB db = client.getDB("example");
DBCollection coll = db.getCollection("exp");
DBObject matchFields = new
BasicDBObject("show.season.episodes.questionEntry.metaTags",
new BasicDBObject("$in", continentList));
DBObject groupFields = new BasicDBObject( "_id",
"$_id").append("episodes",
new BasicDBObject("$push","$show.season.episodes"));
DBObject unwindshow = new BasicDBObject("$unwind","$show");
DBObject unwindsea = new BasicDBObject("$unwind", "$show.season");
DBObject unwindepi = new BasicDBObject("$unwind",
"$show.season.episodes");
DBObject match = new BasicDBObject("$match", matchFields);
DBObject group = new BasicDBObject("$group", groupFields);
AggregationOutput output =
coll.aggregate(unwindshow,unwindsea,unwindepi,match,group);
for (DBObject result : output.results()) {
System.out.println(result);
}

How can be count() used to get the number of array entries in document.?

I want to count number of sub document where type="User.Notice". My database is as below.
i wrote following query but it's returning 1 or 0 always. What's possibly wrong with it.
long countss = eventlist.count(new BasicDBObject("192_168_10_17.type", new BasicDBObject("$eq", "User.Notice")));
System.out.println(countss);
Update:
How can i get all records under particular array. I want all the documents under array `192_168_10_17. can you suggest a way?

First you should unwind 192_168_10_17 and used mongo aggregation as below
db.collectionName.aggregate({
"$unwind": "$192_168_10_17"
}, {
"$match": {
"192_168_10_17.type": "User.Notice"
}
}, {
"$group": {
"_id": "$192_168_10_17.type",
"count": {
"$sum": 1
}
}
}, {
"$project": {
"_id": 0,
"count": "$count"
}
})
Above query return all matching User.Notice count. Now convert this query in java using mongo java aggregation . I tried following java code as below
// unwind 192_168_10_17
DBObject unwind = new BasicDBObject("$unwind", "$192_168_10_17");
// create pipeline operations, with the $match
DBObject match = new BasicDBObject("$match",new BasicDBObject("192_168_10_17.type", "User.Notice"));
// Now the $group operation
DBObject groupFields = new BasicDBObject("_id", "$192_168_10_17.type");
groupFields.put("count", new BasicDBObject("$sum", 1));
DBObject group = new BasicDBObject("$group", groupFields);
// build the $projection operation
DBObject fields = new BasicDBObject("_id", 0);
fields.put("count", "$count");
DBObject project = new BasicDBObject("$project", fields);
// run aggregation
List < DBObject > pipeline = Arrays.asList(match, group, project);
AggregationOutput output = collectionName.aggregate(pipeline);
for (DBObject result: output.results()) {
System.out.println(result);
}

How to calculate unique elements in collections?

I have collection like
id : 1, url : youtube.com
also one url can be many times,
I need get whole collections and count unique elements
like
youtube 10
google 8
lycos 5
here is the code
public List<URLEntity> findAll() {
List<URLEntity> list = new ArrayList<URLEntity>();
String sort = "searchDate";
String order = "desc";
DBObject sortCriteria = new BasicDBObject(sort, "desc".equals(order) ? -1 : 1);
BasicDBObject query = new BasicDBObject();
DBCursor cursor = mongoCoreService.getDomainCollection().find(query).sort(sortCriteria);
try {
while (cursor.hasNext()) {
DBObject document = cursor.next();
URLEntity entity = new URLEntity();
entity = Converter.toObject(URLEntity.class, document);
list.add(entity);
}
} finally {
cursor.close();
}
return list;
}
thanks

You can achieve this by using the aggregate framework from MongoDB.
db.yourcollection.aggregate({ $group: { _id: '$url', total: {$sum: 1} }})
You'll obtain something like this, that you can manipulate in JAVA:
{
"result" : [
{
"_id" : "youtube.com",
"total" : 10
},
{
"_id" : "google.com",
"total" : 8
},
{
"_id" : "lycos",
"total" : 5
}
],
"ok" : 1
}

Today I found and test answer in java, here is a code
DBCollection mycoll= db.getCollection("domain");
DBObject fields = new BasicDBObject("domain", 1);
DBObject project = new BasicDBObject("$project", fields );
// Now the $group operation
DBObject groupFields = new BasicDBObject( "_id", "$domain");
groupFields.put("total", new BasicDBObject( "$sum", 1));
DBObject group = new BasicDBObject("$group", groupFields);
// run aggregation
AggregationOutput output = mycoll.aggregate(project, group);
System.out.println(output.getCommand().toString());
for (DBObject dbObject : output.results()) {
System.out.println(dbObject);
}