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MongoDB - How to update a single object in the array of objects inside a document

I have the following document structure:
{
"Agencies": [
{
"name": "tcs",
"id": "1",
"AgencyUser": [
{
"UserName": "ABC",
"Code": "ABC40",
"Link": "http.ios.com",
"TotalDownloads": 0
},
{
"UserName": "xyz",
"Code": "xyz20",
"Link": "http.ios.com",
"TotalDownloads": 0
}
]
}
]
}
Like I have multiple agencies and each agency contains a list of agents.
What I am trying is to pass the Code and update the TotalDownloads field of the agent that matches the code.
For example, if someone uses the code ABC40 so I need to update the field TotalDownloads of the agent called "ABC".
What I have tried is as below:
public virtual async Task UpdateAgentUsersDownloadByCode(string Code)
{
var col = _db.GetCollection<Agencies>(Agencies.DocumentName);
FilterDefinition<Agencies> filter = Builders<Agencies>.Filter.Eq("AgencyUsers.Code", Code);
UpdateDefinition<Agencies> update = Builders<Agencies>.Update.Inc(x => x.AgencyUsers.FirstOrDefault().TotalDownloads, 1);
await col.UpdateOneAsync(filter, update);
}
It is giving me the following error:
Unable to determine the serialization information for x => x.AgencyUsers.FirstOrDefault().TotalDownloads.
Where I'm wrong?

Note: From the attached sample document, the array property name: AgencyUser is not matched with the property name that you specified in the update operation, AgencyUsers.
Use arrayFilters with $[<identifier>] positional filtered operator to update the element(s) in the array.
MongoDB syntax
db.Agencies.update({
"AgencyUsers.Code": "ABC40"
},
{
$inc: {
"AgencyUsers.$[agencyUser].TotalDownloads": 1
}
},
{
arrayFilters: [
{
"agencyUser.Code": "ABC40"
}
]
})
Demo # Mongo Playground
MongoDB .NET Driver syntax
UpdateDefinition<Agencies> update = Builders<Agencies>.Update
.Inc("AgencyUsers.$[agencyUser].TotalDownloads", 1);
UpdateOptions updateOptions = new UpdateOptions
{
ArrayFilters = new[]
{
new BsonDocumentArrayFilterDefinition<Agencies>(
new BsonDocument("agencyUser.Code", Code)
)
}
};
UpdateResult result = await col.UpdateOneAsync(filter, update, updateOptions);
Demo

Elasticsearch NEST MultiGet across multiple indexes

I want to run a MultiGet (mget) search query on several IDs across two indexes. This is because I have two indexes, but I don't know which index contains my ID. This is the query:
GET _mget
{
"docs" : [
{
"_id": "id1",
"_index": "index1"
},
{
"_id": "id1",
"_index": "index2"
}
/* .... */
]
}
The query works great manually - I get the results and I just ignore the result that returns found: false.
Nest does not support this functionality, only on one index. So I tried to use the low-level client to achieve this, like so:
var data = PostData.Serializable(new
{
docs = new[]
{
new {
_id = "1",
_index = "index1"
},
new
{
_id = "1",
_index = "index2"
}
}
});
var response = await lowLevelClient.MultiGetAsync<MultiGetResponse>(data);
However, I'm getting the following exception: Elasticsearch.Net.UnexpectedElasticsearchClientException: 'Constructor on type 'Nest.MultiGetResponseFormatter' not found.'.
Is this the right way to achieve what I want?

Following will help you achieve what you are looking for with NEST
var request = new MultiGetRequest();
request.Documents = new IMultiGetOperation[]
{
new MultiGetOperation<object>("id1") { Index = "index1" },
new MultiGetOperation<object>("id1") { Index = "index2" },
};
var multiGetResponse = await client.MultiGetAsync(request);

Merge parent field and its nested array field in mongodb

I have a collection like below
{
"id":"5fd13c33ac0277c435117519",
"content":"test",
"votes":[
{
"user":"22",
"isLike":true
},
{
"user":"25",
"isLike":false
},
{
"user":"43",
"isLike":false
}
]
},
{
"id":"5fd13c33ac0277c435237443",
"content":"test 2",
"votes":[
{
"user":"25",
"isLike":true
},
{
"user":"43",
"isLike":false
}
]
}
How can I get the result below with c# driver by querying over votes.user -ie. 25- and then merge those 2 fields from parent and nested array?
{
"id":"5fd13c33ac0277c435117519",
"isLike":false
},
{
"id":"5fd13c33ac0277c435237443",
"isLike":true
}
EDIT: I've got the result after some try and fails on mongoplayground.net, stil not sure how to convert it over c# driver.
db.collection.aggregate([
{
$unwind: "$votes"
},
{
$match: {
"votes.user": "25"
}
},
{
$replaceWith: {
id: "$id",
isLike: "$votes.isLike"
}
}
])

I've managed it like below and wanted to share if someone needs it in the future.
I personally decided to go one-to-many path with separated vote collection after some readings.
var match = new BsonDocument("votes.user", 25);
var replace = new BsonDocument(new List<BsonElement> {
new BsonElement("id", "$id"),
new BsonElement("isLike", "$votes.isLike"),
});
return await _collection.Aggregate()
.Unwind(c => c.votes)
.Match(match)
.ReplaceWith<UserVote>(replace)
.ToListAsync();

How to mimic URI query

This may be too basic of a question for SO, but I thought I would ask anyway.
I getting my feet wet with ElasticSearch and am trying to return a single document that has an exact match to my field of interest.
I have the field "StoryText" which is mapped as type "string" and indexed as "not_analyzed".
When I search using a the basic URI query:
123.456.0.789:9200/stories/storyphrases/_search?q=StoryText:"The boy sat quietly"
I return an exact matched document as I expected with a single hit.
However, when I use the search functionality:
GET 123.456.0.789:9200/stories/storyphrases/_search
{
"query" : {
"filtered" : {
"filter" : {
"term" : {
"StoryText" : "The boy sat quietly"
}
}
}
}
}
I get multiple documents returned with many hits (i.e. "The boy sat loudly", "The boy stood quietly" etc. etc.)
Could somebody help me to understand how I need to restructure my search request to mimic the result I get using the basic query parameter?
At present I am using NEST in C# to generate my search request which looks like this
var searchresults = client.Search<stories>(p => p
.Query(q => q
.Filtered(r => r
.Filter(s => s.Term("StoryText", inputtext))
)
)
);
Thanks very much for any and all reads and or thoughts!
UPDATE: Mappings are listed below
GET /stories/storyphrases/_mappings
{
"stories": {
"mappings": {
"storyphrases": {
"dynamic": "strict",
"properties": {
"#timestamp": {
"type": "date",
"format": "date_optional_time"
},
"#version": {
"type": "string"
},
"SubjectCode": {
"type": "string"
},
"VerbCode": {
"type": "string"
},
"LocationCode": {
"type": "string"
},
"BookCode": {
"type": "string"
},
"Route": {
"type": "string"
},
"StoryText": {
"type": "string",
"index": "not_analyzed"
},
"SourceType": {
"type": "string"
},
"host": {
"type": "string"
},
"message": {
"type": "string"
},
"path": {
"type": "string"
}
}
}
}
}
Mick

Well, first off you are executing two different queries here. The first is running in a query context whilst the second is essentially a match_all query executing in a filtered context. If your objective is simply to emulate the first query but by passing a JSON body you will need something like
GET 123.456.0.789:9200/stories/storyphrases/_search
{
"query" : {
"query_string" : {
"query" : "StoryText:'The boy sat quietly'"
}
}
}
To write this simple query using Nest you would use
var searchresults = client.Search<stories>(p => p.QueryString("StoryText:" + inputtext));
or in longer form
var searchresults = client.Search<stories>(p => p
.Query(q => q
.QueryString(qs => qs
.Query("StoryText:" + inputtext)
)
)
);
These both produce the same JSON body and send it to the _search endpoint. Assuming that storyphrases is your Elasticsearch type then you may also wish to include this in your C#.
var searchresults = client.Search<stories>(p => p
.Index("stories")
.Type("storyphrases")
.Query(q => q
.QueryString(qs => qs
.Query("StoryText:" + inputtext)
)
)
);
Having said all that and looking at your filtered query it should do what you expect according to my testing. Is your field definitely not analyzed? Can you post your mapping?

MongoDB: Build query in C# driver

I stacked to build this Mongodb query in C# driver:
{
Location: { "$within": { "$center": [ [1, 1], 5 ] } },
Properties: {
$all: [
{ $elemMatch: { Type: 1, Value: "a" } },
{ $elemMatch: { Type: 2, Value: "b" } }
]
}
}
Something next:
var geoQuery = Query.WithinCircle("Location", x, y, radius);
var propertiesQuery = **?**;
var query = Query.And(geoQuery, propertiesQuery);
Addition:
The above query taken from my another question:
MongoDB: Match multiple array elements
You are welcome to take part in its solution.

Here's how if you want to get that exact query:
// create the $elemMatch with Type and Value
// as we're just trying to make an expression here,
// we'll use $elemMatch as the property name
var qType1 = Query.EQ("$elemMatch",
BsonValue.Create(Query.And(Query.EQ("Type", 1),
Query.EQ("Value", "a"))));
// again
var qType2 = Query.EQ("$elemMatch",
BsonValue.Create(Query.And(Query.EQ("Type", 2),
Query.EQ("Value", "b"))));
// then, put it all together, with $all connection the two queries
// for the Properties field
var query = Query.All("Properties",
new List<BsonValue> {
BsonValue.Create(qType1),
BsonValue.Create(qType2)
});
The sneaky part is that while many of the parameters to the various Query methods expect BsonValues rather than queries, you can create a BsonValue instance from a Query instance by doing something like:
// very cool/handy that this works
var bv = BsonValue.Create(Query.EQ("Type", 1));
The actual query sent matches your original request exactly:
query = {
"Properties": {
"$all": [
{ "$elemMatch": { "Type": 1, "Value": "a" }},
{ "$elemMatch": { "Type": 2, "Value": "b" }}
]
}
}
(I'd never seen that style of $all usage either, but apparently, it sounds like it's just not documented yet.)

While I can confirm that the query you posted works on my machine, the documentation of $all seems to indicate that it shouldn't accept expressions or queries, but only values:
Syntax: { field: { $all: [ <value> , <value1> ... ] }
(The documentation uses <expression> if queries are allowed, compare to $and). Accordingly, the C# driver accepts only an array of BsonValue instead of IMongoQuery.
However, the following query should be equivalent:
{
$and: [
{ "Location": { "$within": { "$center": [ [1, 1], 5 ] } } },
{ "Properties" : { $elemMatch: { "Type": 1, "Value": "a" } } },
{ "Properties" : { $elemMatch: { "Type": 2, "Value": "b" } } }
]
}
Which translates to the C# driver as
var query =
Query.And(Query.WithinCircle("Location", centerX, centerY, radius),
Query.ElemMatch("Properties", Query.And(Query.EQ("Type", 1), Query.EQ("Value", "a"))),
Query.ElemMatch("Properties", Query.And(Query.EQ("Type", 2), Query.EQ("Value", "b"))));