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I need to retrieve MongoDB's object just with filtered's array item

I'm needing to retrieve just with two dates, all the documents from my MongoDB's collection, with the filtered items from the array.
This is an example of 2 of my documents;
{
"_id" : ObjectId("5f18fa823406b7000132d097"),
"last_date" : "22/07/2020 23:48:32",
"history_dates" : [
"22/07/2020 23:48:32",
"22/07/2020 00:18:53",
"23/07/2020 00:49:12",
"23/07/2020 01:19:30"
],
"hostname" : "MyHostname1",
"ip" : "142.0.111.79",
"component" : "C:\\Windows\\System32\\es-ES\\KernelBase.dll.mui",
"process" : "LogonUI.exe",
"date" : "23/07/2020 10:26:04",
}
{
"_id" : ObjectId("5f18fa823406b7000132d098"),
"last_date" : "22/07/2020 23:48:33",
"history_dates" : [
"22/07/2020 23:48:33",
"23/07/2020 00:18:53",
],
"hostname" : "MyHostName2",
"ip" : "142.0.111.54",
"component" : "C:\\Windows\\System32\\es-ES\\KernelBase.dll.mui",
"process" : "svchost.exe",
"date" : "23/07/2020 10:26:04",
}
I'm needing to make a find to my database (Using Spring Data), to retrieve the same objects, but with the "history_dates"'s array filtered between the 2 dates recieved.
For example, if my 2 recieved dates are: "23/07/2020" and "24/07/2020", I want MongoDB to return the next objects;
{
"_id" : ObjectId("5f18fa823406b7000132d097"),
"last_date" : "22/07/2020 23:48:32",
"history_dates" : [
"23/07/2020 00:49:12",
"23/07/2020 01:19:30"
],
"hostname" : "MyHostname1",
"ip" : "142.0.111.79",
"component" : "C:\\Windows\\System32\\es-ES\\KernelBase.dll.mui",
"process" : "LogonUI.exe",
"date" : "23/07/2020 10:26:04",
}
{
"_id" : ObjectId("5f18fa823406b7000132d098"),
"last_date" : "22/07/2020 23:48:33",
"history_dates" : [
"23/07/2020 00:18:53"
],
"hostname" : "MyHostName2",
"ip" : "142.0.111.54",
"component" : "C:\\Windows\\System32\\es-ES\\KernelBase.dll.mui",
"process" : "svchost.exe",
"date" : "23/07/2020 10:26:04",
}
I'm really ignorant about MongoDB's queries, and I have been trying to make this with Spring Data all the week.
UPDATE 1.
Thanks varman, and do you know how can i just retrieve the documents with filtered arrays not empty?

So basically you need to do filter. MongoTemplate offers a lot of operation for mongodb, if some methods don't exist in MongoTemplate, we can go with Bson Document pattern. In that case, try this article: Trick to covert mongo shell query.
Actually you need a Mongo query something like following. Using $addFields one of the methods shown below. But you can use $project, $set etc. Here $addFields overwrites your history_dates. (It uses to add new fields to document too).
{
$addFields: {
history_dates: {
$filter: {
input: "$history_dates",
cond: {
$and: [{
$gt: ["$$this", "23/07/2020"]
},
{
$lt: ["$$this", "24/07/2020"]
}
]
}
}
}
}
}
Working Mongo playground.
You need to convert this into spring data. So #Autowired the MongoTemplate in you class.
#Autowired
MongoTemplate mongoTemplate;
The method is,
public List<Object> filterDates(){
Aggregation aggregation = Aggregation.newAggregation(
a->new Document("$addFields",
new Document("history_dates",
new Document("$filter",
new Document("input","$history_dates")
.append("cond",
new Document("$and",
Arrays.asList(
new Document("$gt",Arrays.asList("$$this","23/07/2020")),
new Document("$lt",Arrays.asList("$$this","24/07/2020"))
)
)
)
)
)
)
).withOptions(AggregationOptions.builder().allowDiskUse(Boolean.TRUE).build());
return mongoTemplate.aggregate(aggregation, mongoTemplate.getCollectionName(YOUR_CLASS.class), Object.class).getMappedResults();
}
Mongo template doesn't provide add methods for $addFields and $filter. So we just go with bson document pattern. I haven't tested this in Spring.

Retrieve all the documents matching the criteria in an array elements which is a subdocument

{
"_id" : ObjectId("577b54816081dd32cd3e2d60"),
"user" : ObjectId("577b54816081dd32cd3e2d5e"),
"journals" : [
{
"title" : "Journal Title2",
"desc" : "desx2",
"feeling" : 3,
"date" : ISODate("2016-07-05T06:32:45.404Z"),
"deleteFl" : true,
"_id" : ObjectId("577b548d6081dd32cd3e2d64")
},
{
"title" : "Journal Title3",
"desc" : "desx3",
"feeling" : 3,
"date" : ISODate("2016-07-05T06:49:00.156Z"),
"deleteFl" : false,
"_id" : ObjectId("577b585c6081dd32cd3e2d6d")
},
{
"title" : "Journal Title4",
"desc" : "desx4",
"feeling" : 3,
"date" : ISODate("2016-07-05T06:49:06.700Z"),
"deleteFl" : false,
"_id" : ObjectId("577b58626081dd32cd3e2d70")
}
]
}
Above is my document structure
now, I need all the journal documents whose deleteFl = false.
I tried in this way using Java Mongo driver
getDatabase().getCollection("journals").find(and(eq("user", user), eq("journals.deleteFl", false)));
but still it gives me back all the documents including "deleteFl": true. any help here ?

Actually, your query returns 1 document, because the data is inside 1 document. What you want is to limit the returning fields of a document (limit subdocuments).
Note: You can do that using elemMatch in the projection, to limit the fields returned by the query. But elemMatch will return just one subdocument. (I posted a deleted wrong answer using elemMatch)
When you want all subdocuments and only specific subdocuments from inside an array, you need to use the aggregation pipeline.
Here is a tested code that does what you want (just change DB and colelction name):
MongoClient mongoClient = new MongoClient();
MongoDatabase db = mongoClient.getDatabase("test");
MongoCollection collection = db.getCollection("test");
Iterable<Document> output = collection.aggregate(asList(
new BasicDBObject("$unwind", "$journals"),
new BasicDBObject("$match", new BasicDBObject("journals.deleteFl", false))
));
for (Document dbObject : output)
{
System.out.println(dbObject);
}

MongoDB update element of nested array

I have a mongo collection named firma which has one of the document structure as below:
{
"_id" : ObjectId("5729af099b3ebf1d0ca7ff05"),
"musteriler" : [
{
"_id" : "de0bf813-b707-4a8d-afc2-9752e05c3aa5",
"yetkiliListesi" : [
{
"_id" : "a5e487fa-2034-4817-94f2-3bd837b76284",
"ad" : "Burak",
"soyad" : "Duman 1",
"cepTel" : "3333333333333",
"mail" : "asdf#asdf.com"
},
{
"_class" : "com.bisoft.entity.MusteriYetkili",
"_id" : "bc4b537d-522a-4c9a-9f67-8ca243e18f46",
"ad" : "Ridvan",
"soyad" : "ENİŞ",
"cepTel" : "222222222222",
"mail" : "asdf#asdf.com"
}
]
}
],
"defaultTimezone" : "Europe/Istanbul"
}
In the above json, I need to update element of second array(yetkiliListesi) which _id = "a5e487fa-2034-4817-94f2-3bd837b76284"
Since I am using a java application(using mongo java driver and spring boot MongoTemplate) to access it and execute this query :
mongoTemplate.updateFirst(Query.query(Criteria.where("_id").is("5729af099b3ebf1d0ca7ff05").and("musteriler.yetkiliListesi._id").is("a5e487fa-2034-4817-94f2-3bd837b76284")),
new Update().set("musteriler.yetkiliListesi.$", yetkiliDBO), Firma.class);
In the above query, yetkiliDBO is a BasicDBObject and its content :
yetkiliDBO = {
'_class': 'com.bisoft.entity.MusteriYetkili',
'_id': "a5e487fa-2034-4817-94f2-3bd837b76284",
'ad': 'wer',
'soyad': 'xyz',
'cepTel': "222222222222",
mail: "asdf#asdf.com"
}
when execute my query I have an error
com.mongodb.WriteConcernException: { "serverUsed" : "192.168.2.250:27017" , "ok" : 1 , "n" : 0 , "updatedExisting" : false , "err" : "cannot use the part (musteriler of musteriler.yetkiliListesi.0) to traverse the element
What I need to do?

You can not use the '$' placeholder when traversing nested arrays.
The positional $ operator cannot be used for queries which traverse more than one array, such as queries that traverse arrays nested within other arrays, because the replacement for the $ placeholder is a single value
source
I would suggest restructuring your data into separate, less-nested collections.

Mongodb: Can't save a new element added into BasicDBList

I am trying to add an element to a BasicDBList array and save it back to Mongodb, but when I check the result, it is not written. What did I do wrong? I use java driver version 2.7.2.
DBObject dbObject = coll.findOne(dbQuery);
BasicDBList unreadMsgs = (BasicDBList) dbObject.get("unreadMsgs");
Logger.debug("before incrementing unreadMsgs" + dbObject.toString());
unreadMsgs.add(new BasicDBObject("id", 1).append("unreadMsg", 1));
Logger.debug("after incrementing unreadMsgs : " + dbObject.toString());
coll.save(dbObject);
Logger.debug("check result: " + coll.findOne(dbQuery).toString());
before incrementing unreadMsgs{ "_id" : { "$oid" : "515c5eb88e3278e9c9d55867"} , "unreadMsgs" : [ ]}
after incrementing unreadMsgs : { "_id" : { "$oid" : "515c5eb88e3278e9c9d55867"} , "unreadMsgs" : [ { "id" : 1 , "unreadMsg" : 1}]}
check result: { "_id" : { "$oid" : "515c5eb88e3278e9c9d55867"} , "unreadMsgs" : [ ]}

The problem is that the coll.save(dbObject) is not updating anything.
It works as an insert and, since the _id already exists in the collection, you are getting a duplicateKey exception (you are just not seeing it because of configuration).
You have to use an update, here is how

The save call should work on that case, but I suggest you use an update with $addToSet operation.
Here's the code:
DBObject addToSetObj = BasicDBObjectBuilder.start()
.push("$addToSet")
.push("unreadMsgs")
.add("id", 1)
.add("unreadMsg", 1)
.pop()
.pop()
.get();
// addToSetObj will be { "$addToSet" : { "unreadMsgs" : { "id" : 1 , "unreadMsg" : 1}}}
coll.update(dbQuery, addToSetObj);
Logger.debug("check result: " + coll.findOne(dbQuery).toString());
Any doubts on how to use addToSet, check this out: http://docs.mongodb.org/manual/reference/operator/addToSet/

Thanks for everybody's answer. I found the real problem. It turns out that my collection is capped, and I am not allowed to insert more data into an existing document in a capped collection. I saw the exception after I changed WriteConcern to FSYNC_SAFE. I changed all my collections to uncapped, and the code works now.

MongoDB JSON array within JSON object field removal

I have a json object as following:
{ "_id" : ObjectId("508806803bb97dc546e6f307"), "user_name" : "user1", "user_id" : 45645645, "likes" : [ { "event_id" : NumberLong("4578541212") },{ "event_id" : NumberLong("4578541213") } ], "dislikes" : [ ] }
I'm trying to delete specific event within likes array via java drivers
tried doing this first in shell:
> db.users.update( {'likes.event_id' : 4578541212}, { '$unset':{'likes.event_id'
:1}})
with no luck...how can I manage doing that?

If you want to just remove the event_id field from the array element:
db.users.update( {'likes.event_id' : 4578541212}, {'$unset':{'likes.$.event_id' :1}})
Use the $pull operator to delete the element:
db.users.update({'likes.event_id': 4578541212}, {'$pull':{likes: {event_id: 4578541212}}})