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Match exact phrase using elasticsearch Nest

I'm using Nest to build a query. I have a class called Event which has a property called Location and a property called Address (a string). So the indices look something like this:
"id" : "something1",
"location": {
"address": "The Club",
}
"id" : "something2",
"location": {
"address": "The Hole",
}
I want to create a query where the user types "The Club" (the location variable) and it only retrieves the first item that has "The Club" as the address
This is my current query
var skip = (page - 1) * rows;
var searchResponse = await _elasticClient.SearchAsync<Event>(s => s
.From(skip)
.Size(rows)
.Query(q => q
.QueryString(qs => qs
.Fields(fields => fields
.Field(f => f.Location.Address)
)
.Analyzer("keyword")
.Query("*" + (location ?? string.Empty) + "*")
)
));
Currently, the query retrieves both objects since it finds "The". Do I need to add something to my index previously or what should I do?
For the record I added this when creating the index but it has no effect
client.Indices.Create(eventsIndex, c => c.Map<Event>(m => m
.Properties(p => p
.Text(t => t
.Name(n => n.Location.Address)
.Analyzer("keyword"))
)
));

I have two suggestions:
1 - Add the stop filter (default language english) that way you won't produce tokens like the term "the", all stopwords will be removed. Now you will only match the term "hotel", the term "the" will be filtered out.
POST _analyze
{
"tokenizer": "standard",
"filter": ["stop"],
"text": ["the hotel"]
}
Token
{
"tokens": [
{
"token": "hotel",
"start_offset": 4,
"end_offset": 9,
"type": "<ALPHANUM>",
"position": 1
}
]
}
2 - Use the default_operator AND in Query String query.

Elasticsearch could not search on string field

I am trying to use NEST to create search query dynamically based on user's input.
I want to add multiple filter in Filter with Term but string field searching is not possible and I cannot find any solution.
Code for example is that, this code try to search on string field an it is not working
var response = await _elasticClient.SearchAsync<CustomerAddressInfo>(p => p
.Query(q => q
.Bool(b => b
.Filter(f => f.Term(t => t.Field(p => p.AccountAddressId).Value(type.AccountAddressId)))
)
)
);
And the other search simple is with integer field and it is working with success
var response = await _elasticClient.SearchAsync<CustomerAddressInfo>(p => p
.Query(q => q
.Bool(b => b
.Filter(f => f.Term(t => t.Field(p => p.CreateUnitId).Value(type.CreateUnitId)))
)
)
);
But; if I search data on string field with Match keyword, again it is successfull on search
var response = await _elasticClient.SearchAsync<CustomerAddressInfo>(p => p
.Query(q => q
.Match(m => m
.Field(f => f.AccountAddressId)
.Query(type.AccountAddressId)
)
)
);
And the question is, how can I give multiple search criteria with Match query method or how can I seach on string field by Term query method on elastic

I am not familiar with NEST, but to search on multiple fields using match query or term query, you can refer following example :
Bool query is used to combine one or more clauses, to know more refer this
Avoid using the term query for text fields.
By default, Elasticsearch changes the values of text fields as part of
analysis. This can make finding exact matches for text field values
difficult.
To search text field values, use the match query instead.
Index Mapping
{
"mappings": {
"properties": {
"name": {
"type": "text"
},
"cost": {
"type": "long"
}
}
}
}
Index data:
{
"name":"apple",
"cost":"40"
}
{
"name":"apple",
"cost":"55"
}
Search Query: Multiple Search criteria with match
{
"query": {
"bool": {
"must": [
{ "match": { "name": "apple" }},
{ "match": { "cost": 40 }}
]
}
}
}
Search on-field by term query
{
"query": {
"bool" : {
"must" :[
{"term" : { "name" : "apple" }},
{"term": { "cost":40 }}
]
}
}
}
Search Result:
"hits": [
{
"_index": "my-index",
"_type": "_doc",
"_id": "3",
"_score": 1.1823215,
"_source": {
"name": "apple",
"cost": "40"
}
}
]

Hey i do not get the whole requirements of yours. But if you want to add multiple condition on filter then you can do like below.
QueryContainer qSs = null;
foreach(var query in queries) // let say queries is list of yours search item
{
qSs &= new TermQuery { Field = "your_field_name", Value = query };
}
var searchResults = await _elasticClient.SearchAsync<CustomerAddressInfo>(s => s
.Query(q => q
.Bool(b => b.Filter(qSs) )
)
);

LINQ Get Average values from IQueryable

I'm new to LINQ and I need to write a LINQ query that returns each project's grade, called notet also the average of all notes.
Here is the query I have:
`var query = _context.Set<EvaluationResult>()
.Include(x => x.RatingLevel)
.Include(x => x.Skill)
.Include(x => x.Evaluation)
.ThenInclude(y => y.Project)
.ThenInclude(z => z.ProjectRatingLevels)
.ThenInclude(a => a.RatingLevel)
.Include(y => y.Evaluation.Project)
.ThenInclude(y => y.Degree)
.Where(x => x.Evaluation.Project.DegreeId == QueriedDegreeId)
.GroupBy(i => new { project = i.Evaluation.Project })
.Select(g => new
{
project = g.Select(y => y.Evaluation.Project.Label)
.Distinct().FirstOrDefault(),
note = Math.Round(((g.Sum(y => (double)y.Skill.Weight * (double)y.RatingLevel.Rate) /
g.Sum(y => (double)y.RatingLevel.Rate)) * 100) /
(double)g.Key.project.ProjectRatingLevels
.Select(z => z.RatingLevel.Rate)
.Max(), 2, MidpointRounding.AwayFromZero)
});
Here is the result:
[
{
"project": "Projet 1",
"note": 42.86
},
{
"project": "Projet 2",
"note": 41.67
},
{
"project": "Projet 3",
"note": 46.67
}
]
What I want is to add another value, average, which is just the Average of all "note" values, like so (the asterisks are just for emphasis):
[
{
"project": "Projet 1",
"note": 42.86,
**"average": 43.73**
},
{
"project": "Projet 2",
"note": 41.67,
**"average": 43.73**
},
{
"project": "Projet 3",
"note": 46.67,
**"average": 43.73**
}
]
MY PROBLEM
I'm stuck trying to calculate an Average of all the returned notes. I have no idea how to proceed. I tried to add an average key in my Select after note and project that reused the note query, like this:
average = g.Average(Math.Round(((g.Sum(... etc
But this gives me type errors: CS1929 'IGrouping<<anonymous type: Project project>, EvaluationResult>' does not contain a definition for average 'Average'. So I'm at an utter loss of what to do.
Can someone point me in the right direction? Am I missing something, like the need to use a Key or something?

Is your goal to do it all in one query ?
The only possible Resultset, with Aggregate and the Aggregated Items, is a GroupBy.
If you want to aggregate all, you want only one group, so you have to have a fictive key,the same one for each item
So Append:
.GroupBy(x => 1) /* makes one group for all, all have the same key */
.Select(g => new { average = g.Average(x => x.notes), items = g.Select(x => x)});
But this is really Forcing the SQL-Server to do the average. You Manifest the items in your memory anyway. So you can also take your existing Resultset, manifested with ToList or ToArray and just compute
var result = <yourquery>.ToList();
double average = result.Average(x => x.notes);
The only difference is, this is done on your CPU, not on the SQL-Server.

Querying a subfield in DocumentDB to sort and get the latest date

To add/expound on my recent question
Below are DocumentDB collections: "delivery"
{
"doc": [
{
"docid": "15",
"deliverynum": "123",
"text": "txxxxxx",
"date": "2019-07-18T12:37:58Z"
},
{
"docid": "17",
"deliverynum": "999",
"text": "txxxxxx",
"date": "2018-07-18T12:37:58Z"
}
],
"id": "123",
"cancelled": false
},
{
"doc": [
{
"docid": "16",
"deliverynum": "222",
"text": "txxxxxx",
"date": "2019-07-18T12:37:58Z"
},
{
"docid": "17",
"deliverynum": "999",
"text": "txxxxxx",
"date": "2019-07-20T12:37:58Z"
}
],
"id": "124",
"cancelled": false
}
I need to search the deliverynum=999 w/ the latest date to get the "id", which in the case above is "124" because it has the latest "date" in the "doc" w/ deliverynum=999.
I was going to do:
var list = await collection.Find(filter).Project(projection).ToListAsync();
then do a LINQ to sort, but the problem here is my projection change the list from my Model Class to BsonDocument even if my projection included all the fields.
Was looking for a way to either get just needed "id" or get the single document.

i believe the following will do the trick. (if i understood your requirement correctly)
var result = collection.Find(x => x.docs.Any(d => d.deliverynum == 999))
.Sort(Builders<Record>.Sort.Descending("docs.date"))
.Limit(1)
.Project(x=>x.Id) //remove this to get back the whole record
.ToList();
update: strongly typed solution
var result = collection.AsQueryable()
.Where(r => r.docs.Any(d => d.deliverynum == 999))
.SelectMany(r => r.docs, (r, d) => new { r.Id, d.date })
.OrderByDescending(x => x.date)
.Take(1)
.Select(x => x.Id)
.ToArray();

Searching using NEST does not return results, when querying on certain fields

I'm developing an .NET application using Elastic Search. I used ES River to index the data.
Results (in Sense) look kinda like this:
{
"_index": "musicstore",
"_type": "songs",
"_id": "J2k-NjXjRa-mgWKAq0RMlw",
"_score": 1,
"_source": {
"songID": 42,
"tempo": "andante",
"metrum": "3/4 E8",
"intonation": "F",
"title": "Song",
"archiveSongNumber": "3684",
"Year": 2000,
"Place": "London"
}
},
To access the indexed data I use NEST queries similar to this:
var result = ElasticClient.Search<Song>(s => s.Query(q => q.Term(p => p.title, "Song")));
I'm having a problem that the query doesn't return any results, when I search for a certain field.
For instance when I search for a title, songID, tempo or archiveSongNumber the query works fine and it returns the same results as Sense, but when I search for Year, Place, metrum, etc. the query doesn't return any results, but it should (Sense does and it should).
Queries like these work (and return the right results):
var result = ElasticClient.Search<Song>(s => s.Query(q => q.Term(p => p.title, "Song")));
var result = ElasticClient.Search<Song>(s => s.Query(q => q.Term(p => p.songID, 42)));
var result = ElasticClient.Search<Song>(s => s.Query(q => q.Term(p => p.archiveSongNumber , "3684")));
Queries like these don't return any results (but they should):
var result = ElasticClient.Search<Song>(s => s.Query(q => q.Term(p => p.Place, "London")));
var result = ElasticClient.Search<Song>(s => s.Query(q => q.Term(p => p.Year, 2000)));
What am I doing wrong? Did I mess up when I was indexing data?
Update:
Mapping looks like this:
{
"musicstore": {
"mappings": {
"songs": {
"properties": {
"Year": {
"type": "long"
},
"Place": {
"type": "string"
},
"archiveSongNumber": {
"type": "string"
},
"songID": {
"type": "long"
},
"intonation": {
"type": "string"
},
"metrum": {
"type": "string"
},
"title": {
"type": "string"
},
"tempo": {
"type": "string"
}
}
}
}
}
}
Update 2:
ES river request looks like this:
PUT /_river/songs_river/_meta
{
"type":"jdbc",
"jdbc": {
"driver":"com.microsoft.sqlserver.jdbc.SQLServerDriver",
"url":"jdbc:sqlserver://ip_address:1433;databaseName=database",
"user":"user",
"password":"password",
"strategy":"simple",
"poll":"300s",
"autocommit":true,
"fetchsize":10,
"max_retries":3,
"max_retries_wait":"10s",
"index":"musicstore",
"type":"songs",
"analysis": {
"analyzer" :{
"whitespace" :{
"type" : "whitespace",
"filter":"lowercase"
}
}
},
"sql":"some_sql_query"
}
}
ES client configuration looks like this:
private static ElasticClient ElasticClient
{
get
{
Uri localhost = new Uri("http://localhost:9200");
var setting = new ConnectionSettings(localhost);
setting.SetDefaultIndex("musicstore").MapDefaultTypeNames(d => d.Add(typeof(Song), "songs"));
setting.SetConnectionStatusHandler(c =>
{
if (!c.Success)
throw new Exception(c.ToString());
});
return new ElasticClient(setting);
}
}

From looking at your mapping, the issue here is most likely that all of your fields are being analyzed when indexing, but you are using term queries with NEST, which are not analyzed, meaning they will only find exact matches. If you don't explicitly specify an analyzer in your mappings, Elasticsearch defaults to the standard analyzer.
When you perform a search in Elasticsearch using a query string, like you're doing in Sense: GET _search/?q=Place:London, a query string query is what's being run by Elasticsearch, which is different than a term query.
From your examples though, it doesn't look like you are actually using query string syntax. You probably want a match query instead:
client.Search<Song>(s => s
.Query(q => q
.Match(m => m
.OnField(p => p.Place)
.Query("London")
)
)
);
If you do however want a query string query like the one you're performing with Sense, than you can use QueryString:
client.Search<Song>(s => s
.Query(q => q
.QueryString(qs => qs
.OnFields(p => p.Place)
.Query("London")
)
)
);
Hope that helps. I suggest checking out the getting started guide, specifically the section on exact values vs. full text.

Add "keyword" suffix to your Term Field :
var result = ElasticClient.Search<Song>(s => s
.Query(q => q
.Term(p => p
.Field(x => x.Year.Suffix("keyword")).Value(2000))));
Try it, it will work!