Download - Elasticsearch 101
(the VERY basics of it)
Elasticsearch is a highly scalable open-source full-text search and analytics engine.
● A cluster is a collection of one or more nodes (servers) that together holds your entire data and provides federated indexing and search capabilities across all nodes.
● A node is a single server that is part of your cluster, stores your data, and participates in the cluster’s indexing and search capabilities.
● An index is a collection of documents that have somewhat similar characteristics.
● A document is a basic unit of information that can be indexed.
● A type is a logical category/partition of your index whose semantics is completely up to you.
cluster
node
index
type
type
document
document
document
document
● Elasticsearch provides the ability to subdivide your index into multiple pieces called shards.
clusternode
Index: shard 1type
document
document
Index: shard 2type
document
document
● Elasticsearch allows you to make one or more copies of your index’s shards into what are called replica shards, or replicas for short.
clusternode
Index: shard 1type
document
document
Index: shard 2type
document
document
Index: shard 1: replicatype
document
document
Index: shard 2: replicatype
document
document
installation
● Java
● http://www.elasticsearch.org/download/
http://localhost:9200/{
"ok": true,
"status": 200,
"name": "Red Lotus",
"version": {
"number": "0.90.13",
"build_hash": "249c9c5e06765c9e929e92b1d235e1ba4dc679fa",
"build_timestamp": "2014-03-25T15:27:12Z",
"build_snapshot": false,
"lucene_version": "4.6"
},
"tagline": "You Know, for Search"
}
http://localhost:9200/_plugin/head/
Create an index named 'movies_1.0.0'
curl XPUT 'http://localhost:9200/movies_1.0.0'
a concise list of all indices and their aliases in your cluster
curl http://localhost:9200/_aliases
Add an index alias
curl XPOST 'http://localhost:9200/_aliases' d '
{
"actions" : [
{
"add" : {
"index" : "movies_1.0.0",
"alias" : "movies"
}
}
]
}'
Create a type called 'movie'curl -XPUT 'http://localhost:9200/movies/movie/_mapping' -d '{
"movie":{
"properties":{
"director":{
"type":"string"
},
"genres":{
"type":"string"
},
"title":{
"type":"string"
},
"year":{
"type":"long"
}
}
}
}'
get mapping of a type
curl XGET 'http://localhost:9200/movies/movie/_mapping'
Create a document
curl XPUT "http://localhost:9200/movies/movie/1" d'
{
"title": "The Godfather",
"director": "Francis Ford Coppola",
"year": 1972,
"genres": ["Adventure"]
}'
Retrieve the document
curl XGET "http://localhost:9200/movies/movie/1"
more data...curl XPUT "http://localhost:9200/movies/movie/1" d'
{
"title": "The Godfather",
"director": "Francis Ford Coppola",
"year": 1972,
"genres": ["Crime", "Drama"]
}'
curl XPUT "http://localhost:9200/movies/movie/2" d'
{
"title": "Lawrence of Arabia",
"director": "David Lean",
"year": 1962,
"genres": ["Adventure", "Biography", "Drama"]
}'
curl XPUT "http://localhost:9200/movies/movie/3" d'
{
"title": "To Kill a Mockingbird",
"director": "Robert Mulligan",
"year": 1962,
"genres": ["Crime", "Drama", "Mystery"]
}'
curl XPUT "http://localhost:9200/movies/movie/4" d'
{
"title": "Apocalypse Now",
"director": "Francis Ford Coppola",
"year": 1979,
"genres": ["Drama", "War"]
}'
curl XPUT "http://localhost:9200/movies/movie/5" d'
{
"title": "Kill Bill: Vol. 1",
"director": "Quentin Tarantino",
"year": 2003,
"genres": ["Action", "Crime", "Thriller"]
}'
curl XPUT "http://localhost:9200/movies/movie/6" d'
{
"title": "The Assassination of Jesse James by the Coward Robert Ford",
"director": "Andrew Dominik",
"year": 2007,
"genres": ["Biography", "Crime", "Drama"]
}'
Querying
Show all
curl XGET 'http://localhost:9200/movies/_search' d '{
"query": {
"match_all": {}
}
}'
Search request bodycurl XPOST "http://localhost:9200/_search" d'
{
"query": {
"query_string": {
"query": "kill"
}
}
}'
Specifying fields to search in
curl XPOST "http://localhost:9200/_search" d'
{
"query": {
"query_string": {
"query": "ford",
"fields": ["title"]
}
}
}'
Filtering
Filtering sample 1curl XPOST "http://localhost:9200/_search" d'
{
"query": {
"filtered": {
"query": {
"match_all": {
}
},
"filter": {
"term": { "year": 1962 }
}
}
}
}'
Filtering sample 2curl XPOST "http://localhost:9200/_search" d'
{
"query": {
"filtered": {
"query": {
"query_string": {
"query": "drama"
}
},
"filter": {
"term": { "year": 1962 }
}
}
}
}'
references
http://joelabrahamsson.com/elasticsearch101/
http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/_basic_concepts.
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