Elastic stack can be used with beats to fetch file, network and system information etc. It can be connected to existing application to monitor the application performance as well as to create a great dashboard to monitor key performance indicators. We can also use it as a standalone system by pushing the data from any RDBMS or file based data source. We can not only show or search data but can also perform analysis on top of that.

1. Elasticsearch
Anurag Srivastava

2. What
● Full-text Search Engine
● NoSQL Database
● Analytics Engine
● Easy to Scale
● RESTFul interface
● Schemaless
● Inverted Index
● Near Real Time
● ELK Stack

3. Where
● Elasticsearch as the primary back end
for your website
● Adding Elasticsearch to an existing
system
● Elasticsearch as the back end of a
ready-made solution built around it

4. ElasticsearchClients
● Java
● PHP
● Perl
● Python
● .NET
● Ruby
● JavaScript

5. Use Cases
● Online Web Store
● Price Alerting Platform
● Analytics / Business-intelligence
● Central Log Management

6. Basic Concepts
● Cluster
● Node
● Index
● Type
● Document

7. Comparison to RDBMS

8. Shard

9. Shard

10. The Rest API
● Check your cluster, node, and index health, status, and statistics
● Administer your cluster, node, and index data and metadata
● Perform CRUD (Create, Read, Update, and Delete) and search
operations against your indexes
● Execute advanced search operations such as paging, sorting,
filtering, scripting, aggregations, and many others

11. Cluster Health
● Health: GET /_cat/health?v
● nodes in our cluster: GET /_cat/nodes?v

12. Index Listing
● GET /_cat/indices?v
health status index uuid pri rep docs.count
docs.deleted store.size pri.store.size

13. Create Index
● PUT /customer?pretty

14. Index a document
PUT /customer/external/1?pretty
{
"name": "John Doe"
}

15. Delete Index
● DELETE /customer?pretty

16. Once again
PUT /customer
PUT /customer/external/1
{
"name": "John Doe"
}
GET /customer/external/1
DELETE /customer

17. Replacing Document
PUT /customer/external/1?pretty
{
"name": "John Doe"
}

18. Updating
Document
POST /customer/external/1/_update?pretty
{
"doc": { "name": "Jane Doe", "age": 20 }
}
POST /customer/external/1/_update?pretty
{
"script" : "ctx._source.age += 5"
}
In the above example, ctx._source refers to the current source
document that is about to be updated.

19. Deleting Document
● DELETE /customer/external/2?pretty

20. Loading data
curl -H "Content-Type: application/json" -XPOST
'localhost:9200/bank/account/_bulk?pretty&refresh' --data-binary
"@accounts.json"

21. Search API ● REST request URI
● REST request body

22. REST request URI
GET twitter/tweet/_search?q=user:kimchy

23. REST request body
GET /twitter/tweet/_search
{
"query" : {
"term" : { "user" : "kimchy" }
}
}

24. Query
Language
GET /bank/_search
{
"query": { "match_all": {} }
}
{
"query": { "match_all": {} },
"from": 10,
"size": 10
}
{
"query": { "match_all": {} },
"sort": { "balance": { "order": "desc" } }
}

25. Executing
Searches GET /bank/_search
{
"query": { "match_all": {} },
"_source": ["account_number", "balance"]
}

26. Executing Searches
GET /bank/_search
{
"query": { "match": { "address": "mill" } }
}
GET /bank/_search
{
"query": { "match": { "account_number": 20 } }
}

27. Executing
Searches
GET /bank/_search
{
"query": { "match": { "address": "mill lane" } }
}
GET /bank/_search
{
"query": { "match_phrase": { "address": "mill lane" } }
}

28. Wildcard
Query
GET /bank/_search
{
"query": { "wildcard": { "address": "Lu?know" } }
}
GET /bank/_search
{
"query": { "wildcard": { "address": "Lu*w" } }
}

29. Boolean
Query
GET /bank/_search
{
"query": {
"bool": {
"must": [
{ "match": { "address": "mill" } },
{ "match": { "address": "lane" } }
]
}
}
}

30. Boolean Query
GET /bank/_search
{
"query": {
"bool": {
"should": [
{ "match": { "address": "mill" } },
{ "match": { "address": "lane" } }
]
}
}
}

31. Boolean
Query
GET /bank/_search
{
"query": {
"bool": {
"must_not": [
{ "match": { "address": "mill" } },
{ "match": { "address": "lane" } }
]
}
}
}

32. Boolean Query GET /bank/_search
{
"query": {
"bool": {
"must": [
{ "match": { "age": "40" } }
],
"must_not": [
{ "match": { "state": "ID" } }
]
}
}}

33. Executing Filter GET /bank/_search
{
"query": {
"bool": {
"must": { "match_all": {} },
"filter": {
"range": {
"balance": {
"gte": 20000,
"lte": 30000
}
}}}}}

34. Aggregation Aggregations provide the ability to
group and extract statistics from
your data.

35. Aggregation
POST mapping/_search?size=0
{
"aggs" : {
"msehat_app" : {
"terms" : {
"field" : "district_name_hi"
}
}
}
}

36. Aggregation
POST mapping/_search?size=0
{
"aggs" : {
"avg_grade" : { "avg" : { "field" : "total_ashas" } }
}
}