The document discusses Elasticsearch and the .NET NEST client library for interacting with Elasticsearch from .NET code. It explains that NEST provides strongly typed requests and responses for Elasticsearch and supports various query types, including full text search, term level queries, geo queries, and script queries. Examples are shown of implementing queries like match, term, and geo distance using the low-level Elasticsearch REST API versus using the higher level NEST API.

2. Обо мне
.Net Fullstack developer,
MSP
C#
F#JS
AzureASP.NET

3. Http
Lucene

4. Why ?

7. Relational DB
▪ Databases
▪ Tables
▪ Rows
▪ Columns
Elastic Search
▪ Indexes
▪ Types
▪ Documents
▪ Fields

9. ▪ Low-level client
▪ Generated from the official REST
API spec
▪ Unlike NEST, does not provide typed
request and response objects
▪ High level
▪ Strongly typed requests and
responses
▪ Advanced functionality
Elasticsearch .NET NEST

15. ▪ Full text
▪ Term level
▪ Span
▪ Compound
▪ Geo
▪ Joining
▪ Specialized
Elasticsearch .NET
GET /_search
{
"query": {
"match" : {
"message" : “hellow world"
}
}
}
new MatchQuery
{
Field = Field<Project>(p => p.Description),
Query = "hello world",
}

16. ▪ Full text
▪ Term level
▪ Span
▪ Compound
▪ Geo
▪ Joining
▪ Specialized
Elasticsearch .NET
"query": {
"term": {
"user": {
"value": "Kimchy",
"boost": 1.0
}
}
}
new TermQuery
{
Boost = 1.1,
Field = Field<Project>(p => p.Description),
Value = "project description"
}

17. ▪ Full text
▪ Term level
▪ Span
▪ Compound
▪ Geo
▪ Joining
▪ Specialized
Elasticsearch .NET
{
"query": {
"span_term" : { "user" : { "value" : "kimchy", "boost" : 2.0 } }
}
}
new SpanTermQuery
{
Name = "named_query",
Boost = 1.1,
Value = "kimchy",
Field = "user"
}

18. ▪ Full text
▪ Term level
▪ Span
▪ Compound
▪ Geo
▪ Joining
▪ Specialized
Elasticsearch .NET
POST _search
{
"query": {
"bool" : {
"must" : {
"term" : { "user" : "kimchy" }
},
"filter": {
"term" : { "tag" : "tech" }
},
"must_not" : {
"range" : {
"age" : { "gte" : 10, "lte" : 20 }
}
},
"should" : [
{ "term" : { "tag" : "wow" } },
{ "term" : { "tag" : "elasticsearch" } }
],
"minimum_should_match" : 1,
"boost" : 1.0
}
}
}

19. ▪ Full text
▪ Term level
▪ Span
▪ Compound
▪ Geo
▪ Joining
▪ Specialized
Elasticsearch .NET
new GeoDistanceQuery
{
Boost = 1.1,
Name = "named_query",
Field = Infer.Field<Project>(p => p.Location),
DistanceType = GeoDistanceType.Arc,
Location = new GeoLocation(34, -34),
Distance = "200.0m",
ValidationMethod =
GeoValidationMethod.IgnoreMalformed
}

20. ▪ Full text
▪ Term level
▪ Span
▪ Compound
▪ Geo
▪ Joining
▪ Specialized
Elasticsearch .NET
new NestedQuery
{
Name = "named_query",
Boost = 1.1,
InnerHits = new InnerHits { Explain = true },
Path = Field<Project>(p => p.CuratedTags),
Query = new TermsQuery
{
Field = Field<Project>(p =>
p.CuratedTags.First().Name),
Terms = new[] { "lorem", "ipsum" }
},
IgnoreUnmapped = true
}

21. ▪ Full text
▪ Term level
▪ Span
▪ Compound
▪ Geo
▪ Joining
▪ Specialized
Elasticsearch .NET
{
"script": {
"_name": "named_query",
"boost": 1.1,
"script": {
"source": "doc['numberOfCommits'].value > param1",
"params": {
"param1": 50
}
}
}
}
new ScriptQuery
{
Name = "named_query",
Boost = 1.1,
Source = _templateString,
Params = new Dictionary<string, object>
{
{ "param1", 50 }
}
}