how to index for specific fields of documents using elasticsearch - elasticsearch

Question

My requirement is to store specific fields of document to index in elasticsearch.
Example:
My document is
{
"name":"stev",
"age":26,
"salary":25000
}
This is my document but i don't want indexing total document.I want store only name field.
I created one index emp and write mapping like below
"person" : {
"_all" : {"enabled" : false},
"properties" : {
"name" : {
"type" : "string", "store" : "yes"
}
}
}
When see the index document
{
"took": 1,
"timed_out": false,
"_shards": {
"total": 2,
"successful": 2,
"failed": 0
},
"hits": {
"total": 2,
"max_score": 1,
"hits": [
{
"_index": "test",
"_type": "test",
"_id": "AU1_p0xAq8r9iH00jFB_",
"_score": 1,
"_source": { }
}
,
{
"_index": "test",
"_type": "test",
"_id": "AU1_lMDCq8r9iH00jFB-",
"_score": 1,
"_source": { }
}
]
}
}
name fields is not generated,Why?
any one help to me

Answer 1

It's hard to tell what you're doing wrong from what you posted, but I can give you an example that works.
Elasticsearch will, by default, index whatever source documents you give it. Every time it sees a new document field, it will create a mapping field with sensible defaults, and it will index them by default as well. If you want to exclude fields, you can set "index": "no" and "store": "no" in the mapping for each field you want to exclude. If you want that behavior to be the default for every field, you can use the "_default_" property for specifying that fields not be stored (though I couldn't get it to work for not indexing).
You probably also will want to disable "_source", and use the "fields" parameter in your search queries.
Here is an example. The index definition looks like this:
PUT /test_index
{
"mappings": {
"person": {
"_all": {
"enabled": false
},
"_source": {
"enabled": false
},
"properties": {
"name": {
"type": "string",
"index": "analyzed",
"store": "yes"
},
"age": {
"type": "integer",
"index": "no",
"store": "no"
},
"salary": {
"type": "integer",
"index": "no",
"store": "no"
}
}
}
}
}
Then I can add a few documents with the bulk api:
POST /test_index/person/_bulk
{"index":{"_id":1}}
{"name":"stev","age":26,"salary":25000}
{"index":{"_id":2}}
{"name":"bob","age":30,"salary":28000}
{"index":{"_id":3}}
{"name":"joe","age":27,"salary":35000}
Since I disabled "_source", a simple query will return only ids:
POST /test_index/_search
...
{
"took": 1,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"failed": 0
},
"hits": {
"total": 3,
"max_score": 1,
"hits": [
{
"_index": "test_index",
"_type": "person",
"_id": "1",
"_score": 1
},
{
"_index": "test_index",
"_type": "person",
"_id": "2",
"_score": 1
},
{
"_index": "test_index",
"_type": "person",
"_id": "3",
"_score": 1
}
]
}
}
But if I specify that I want the "name" field, I'll get it:
POST /test_index/_search
{
"fields": [
"name"
]
}
...
{
"took": 1,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"failed": 0
},
"hits": {
"total": 3,
"max_score": 1,
"hits": [
{
"_index": "test_index",
"_type": "person",
"_id": "1",
"_score": 1,
"fields": {
"name": [
"stev"
]
}
},
{
"_index": "test_index",
"_type": "person",
"_id": "2",
"_score": 1,
"fields": {
"name": [
"bob"
]
}
},
{
"_index": "test_index",
"_type": "person",
"_id": "3",
"_score": 1,
"fields": {
"name": [
"joe"
]
}
}
]
}
}
You can prove to yourself that the other fields were not stored by running:
POST /test_index/_search
{
"fields": [
"name", "age", "salary"
]
}
which will return the same result. I can also prove that the "age" field wasn't indexed by running this query, which would return a document if "age" had been indexed:
POST /test_index/_search
{
"fields": [
"name", "age"
],
"query": {
"term": {
"age": {
"value": 27
}
}
}
}
...
{
"took": 1,
"timed_out": false,
"_shards": {
"total": 1,
"successful": 1,
"failed": 0
},
"hits": {
"total": 0,
"max_score": null,
"hits": []
}
}
Here is a bunch of code I used for playing around with this. I wanted to use a _default mapping and/or field to handle this without having to specify the settings for each field. I was able to make it work in terms of not storing data, but each field was still indexed.
http://sense.qbox.io/gist/d84967923d6c0757dba5f44240f47257ba2fbe50