elasticsearch - equivalent of "facets" "statistical" for aggregations - elasticsearch

What is the equivalent of "facets" "statistical" fields using aggregations?
"facets": {
"text": {
"statistical": {
"script": "doc['text'].values.size()"
}
}
}

You need to use the stats aggregation
"aggs": {
"text": {
"stats": {
"script": "doc['text'].values.size()"
}
}
}

Related

Filter and sort based on attributes in Terms lookup document in Elastic Search

I have some documents in my index:
POST "/index/thing/_bulk" -s -d'
{ "index":{ "_id": 1 } }
{ "title":"One thing"}
{ "index":{ "_id": 2 } }
{ "title":"Second thing"}
{ "index":{ "_id": 3 } }
{ "title":"Three things"}
{ "index":{ "_id": 4 } }
{ "title":"And so fourth"}
{ "index":{ "_id": 5 } }
{ "title":"Five things"}
'
I also have documents which contain a users collection which are linked to the other documents (things) through the documents id attribute like so:
PUT /index/collection/1
{
"items": [
{"id": 1, "time_added": "2017-08-07T09:07:15.000Z", "condition": "fair"},
{"id": 3, "time_added": "2019-08-07T09:07:15.000Z", "condition": "good"},
{"id": 4, "time_added": "2016-08-07T09:07:15.000Z", "condition": "poor"}
]
}
I then use a terms lookup to get all the things in a users collection like so:
GET /documents/_search
{
"query" : {
"terms" : {
"_id" : {
"index" : "index",
"type" : "collection",
"id" : 1,
"path" : "items.id"
}
}
}
}
This works fine. I get the three documents in the collection and can search, sort and use aggregations like I want.
But is there a way to aggregate, filter and sort those documents based on the attributes (time_added or condition in this case) in the collection document? Say I wanted to sort based on time_added or filter for condition=="good" from the collection?
Maybe a script that can be applied to collection to sort or filter the items in there? It feels like this is getting pretty close to sql like left-join, so maybe Elastic Search is the wrong tool?
It looks like you need the nested data type
Taking your data as an example:
Without nested type:
POST collection/_bulk?filter_path=_
{"index":{}}
{"items":[{"id":11,"time_added":"2017-08-07T09:07:15.000Z","condition":"fair"},{"id":13,"time_added":"2019-08-07T09:07:15.000Z","condition":"good"},{"id":14,"time_added":"2016-08-07T09:07:15.000Z","condition":"poor"}]}
{"index":{}}
{"items":[{"id":21,"time_added":"2017-09-07T09:07:15.000Z","condition":"fair"},{"id":23,"time_added":"2019-09-07T09:07:15.000Z","condition":"good"},{"id":24,"time_added":"2016-09-07T09:07:15.000Z","condition":"poor"}]}
{"index":{}}
{"items":[{"id":31,"time_added":"2017-10-07T09:07:15.000Z","condition":"fair"},{"id":33,"time_added":"2019-10-07T09:07:15.000Z","condition":"good"},{"id":34,"time_added":"2016-10-07T09:07:15.000Z","condition":"poor"}]}
{"index":{}}
{"items":[{"id":41,"time_added":"2017-11-07T09:07:15.000Z","condition":"fair"},{"id":43,"time_added":"2019-11-07T09:07:15.000Z","condition":"good"},{"id":44,"time_added":"2016-11-07T09:07:15.000Z","condition":"poor"}]}
{"index":{}}
{"items":[{"id":51,"time_added":"2017-12-07T09:07:15.000Z","condition":"fair"},{"id":53,"time_added":"2019-12-07T09:07:15.000Z","condition":"good"},{"id":54,"time_added":"2016-12-07T09:07:15.000Z","condition":"poor"}]}
Query (you'd get incorrect results - expected one, got five):
GET collection/_search
{
"query": {
"bool": {
"must": [
{
"term": {
"items.condition": {
"value": "good"
}
}
},
{
"range": {
"items.time_added": {
"lte": "2019-09-01"
}
}
}
]
}
}
}
Aggregation (incorect results - look at the first bucket "2016-08-01T00:00:00.000Z" - it contains 3 CONDITION sub-buckets with every condition type)
GET collection/_search
{
"size": 0,
"aggs": {
"DATE": {
"date_histogram": {
"field": "items.time_added",
"calendar_interval": "month"
},
"aggs": {
"CONDITION": {
"terms": {
"field": "items.condition.keyword",
"size": 10
}
}
}
}
}
}
With nested type
DELETE collection
PUT collection
{
"mappings": {
"properties": {
"items": {
"type": "nested"
}
}
}
}
# and POST the same data from above
Query (returns just one result)
GET collection/_search
{
"query": {
"nested": {
"path": "items",
"query": {
"bool": {
"must": [
{
"term": {
"items.condition": {
"value": "good"
}
}
},
{
"range": {
"items.time_added": {
"lte": "2019-09-01"
}
}
}
]
}
}
}
}
}
Aggregation (the first date bucket contains just one CONDITION sub-bucket)
GET collection/_search
{
"size": 0,
"aggs": {
"ITEMS": {
"nested": {
"path": "items"
},
"aggs": {
"DATE": {
"date_histogram": {
"field": "items.time_added",
"calendar_interval": "month"
},
"aggs": {
"CONDITION": {
"terms": {
"field": "items.condition.keyword",
"size": 10
}
}
}
}
}
}
}
}
Hope that helps :)

ElasticSearch - How can I reuse script_fields field in aggregation?

It is possible to use a script_field to compute a field, 'emp_salary', and use in an aggregation query? Here's an example.
I have a script_fields script to compute the 'emp_salary', and I want to use it in the aggregation sub query but I get
{
"query": {
"term": {
"name.keyword": "John"
}
},
"script_fields": {
"emp_salary": {
"script": {
"lang": "painless",
"source": """return 1"""
}
}
},
"aggs": {
"average": {
"avg": {
"field": "_field['emp_salary']"
}
}
}
}
but I get null for the 'emp_salary'. Am I accessing the field value wrong?
"aggregations": {
"average": {
"value": null
}
}
Thanks

Can We Apply Bucket Selector Aggregation on Nested Aggregation in ElasticSearch?

I want to use PipeLine Aggregation(Bucket Selector Aggregation) to Nested Field Aggregation in ElasticSearch 2.4. I want to do something similar to below but I am not successful. Could you please suggest me if it is possible to do the PipeLine Aggregation in the nested field?
{
"size": 0,
"aggregations": {
"totalPaidAmount": {
"nested": {
"path": "count"
},
"aggregations": {
"paidAmountTotal": {
"sum": {
"field": "count.totalPaidAmount"
}
},
"paidAmount_filter": {
"bucket_selector": {
"script": {
"inline": "amount > 5000000"
},
"buckets_path": {
"amount": "paidAmountTotal"
}
}
}
}
}
}
}
I found the solution for the query. Actually, bucket selector Aggregation should be parallel to the nested aggregation and path should be referenced by '>' as shown below:
{
"size": 0,
"aggregations": {
"amount": {
"terms": {
"field": "countId",
"size": 0
},
"aggregations": {
"totalPaidAmount": {
"nested": {
"path": "count"
},
"aggregations": {
"paidAmountTotal": {
"sum": {
"field": "count.totalPaidAmount"
}
}
}
},
"paidAmount_filter": {
"bucket_selector": {
"script": {
"inline": "amount > 1000"
},
"buckets_path": {
"amount": "totalPaidAmount>paidAmountTotal"
}
}
}
}
}
}
}
You are missing params in script value. so, paidAmount_filter should look like:
"bucket_filter": {
"bucket_selector": {
"buckets_path": {
"amount ": "paidAmountTotal"
},
"script": "params.amount > 5000000"
}
}

How to return only aggregation stats in an ElasticSearch query?

Is it possible to exclude documents from an aggregation query? I just need to know "count" and "sum" and do not need hits. I did it like this:
{
"query": {
"match_all": {
}
},
"aggs": {
"my_agg": {
"stats": {
"field": "country_id"
}
}
}
}
To focus only on aggregation with a match_all query, you could simply use "size":0 (this specifies you want no query results) with no query:
curl -XPOST "http://localhost:9200/indexname/doctype/_search" -d'
{
"size": 0,
"aggs": {
"my_agg": {
"stats": {
"field": "country_id"
}
}
}
}'
Add to your query ?search_type=count.
For example:
GET /my_index/countries/_search?search_type=count
{
"query": {
"match_all": {
}
},
"aggs": {
"my_agg": {
"stats": {
"field": "country_id"
}
}
}
}

Multiple filters and an aggregate in elasticsearch

How can I use a filter in connection with an aggregate in elasticsearch?
The official documentation gives only trivial examples for filter and for aggregations and no formal description of the query dsl - compare it e.g. with postgres documentation.
Through trying out I found following query, which is accepted by elasticsearch (no parsing errors), but ignores the given filters:
{
"filter": {
"and": [
{
"term": {
"_type": "logs"
}
},
{
"term": {
"dc": "eu-west-12"
}
},
{
"term": {
"status": "204"
}
},
{
"range": {
"#timestamp": {
"from": 1398169707,
"to": 1400761707
}
}
}
]
},
"size": 0,
"aggs": {
"time_histo": {
"date_histogram": {
"field": "#timestamp",
"interval": "1h"
},
"aggs": {
"name": {
"percentiles": {
"field": "upstream_response_time",
"percents": [
98.0
]
}
}
}
}
}
}
Some people suggest using query instead of filter. But the official documentation generally recommends the opposite for filtering on exact values. Another issue with query: while filters offer an and, query does not.
Can somebody point me to documentation, a blog or a book, which describe writing non-trivial queries: at least an aggregate plus multiple filters.
I ended up using a filter aggregation - not filtered query. So now I have 3 nested aggs elements.
I also use bool filter instead of and as recommended by #alex-brasetvik because of http://www.elasticsearch.org/blog/all-about-elasticsearch-filter-bitsets/
My final implementation:
{
"aggs": {
"filtered": {
"filter": {
"bool": {
"must": [
{
"term": {
"_type": "logs"
}
},
{
"term": {
"dc": "eu-west-12"
}
},
{
"term": {
"status": "204"
}
},
{
"range": {
"#timestamp": {
"from": 1398176502000,
"to": 1400768502000
}
}
}
]
}
},
"aggs": {
"time_histo": {
"date_histogram": {
"field": "#timestamp",
"interval": "1h"
},
"aggs": {
"name": {
"percentiles": {
"field": "upstream_response_time",
"percents": [
98.0
]
}
}
}
}
}
}
},
"size": 0
}
Put your filter in a filtered-query.
The top-level filter is for filtering search hits only, and not facets/aggregations. It was renamed to post_filter in 1.0 due to this quite common confusion.
Also, you might want to look into this post on why you often want to use bool and not and/or: http://www.elasticsearch.org/blog/all-about-elasticsearch-filter-bitsets/
more on #geekQ 's answer: to support filter string with space char,for multipal term search,use below:
{ "aggs": {
"aggresults": {
"filter": {
"bool": {
"must": [
{
"match_phrase": {
"term_1": "some text with space 1"
}
},
{
"match_phrase": {
"term_2": "some text with also space 2"
}
}
]
}
},
"aggs" : {
"all_term_3s" : {
"terms" : {
"field":"term_3.keyword",
"size" : 10000,
"order" : {
"_term" : "asc"
}
}
}
}
} }, "size": 0 }
Just for reference, as for the version 7.2, I tried with something as follows to achieve multiple filters for aggregation:
filter aggregation to filter for aggregation
use bool to set up the compound query
POST movies/_search?size=0
{
"size": 0,
"aggs": {
"test": {
"filter": {
"bool": {
"must": {
"term": {
"genre": "action"
}
},
"filter": {
"range": {
"year": {
"gte": 1800,
"lte": 3000
}
}
}
}
},
"aggs": {
"year_hist": {
"histogram": {
"field": "year",
"interval": 50
}
}
}
}
}
}

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