I am trying to get a list of users who has as their last activity "connect". Ideally, I want this as a metric viz or a data table in Kibana showing the number of users that connected last and the list of them, respectively. I have, however, given up being able to do this in Kibana. I can get something similar directly from Elasticsearch using a terms aggregation followed by top_hits as below. But the problem is, even though I am sorting the top_hits by #timestamp, the resulting document in NOT the most recent.
{
"size" : 0,
"sort": { "#timestamp": {"order": "desc"} },
"aggs" : {
"by_user" : {
"terms" : {
"field" : "fields.username.keyword",
"size" : 1
},
"aggs": {
"last_message": {
"top_hits": {
"sort": [
{
"#timestamp": {
"order": "desc"
}
}
],
"_source": {
"includes": ["fields.username.keyword", "#timestamp", "status"]
},
"size": 1
}
}
}
}
}
}
Is there a way to do this directly in Kibana?
How can I make sure top_hits gives me the latest results, rather than the "most relevant"?
I think what you want is field collapsing, which is faster than an aggregation.
Something like this should work for your use case:
GET my-index/_search {
"query": {
"match_all": { }
},
"collapse" : {
"field" : "fields.username.keyword"
},
"sort": [ {
"#timestamp": {
"order": "desc"
}
} ] }
I might be missing something, but I don't think Kibana supports this at the moment.
Related
TL;DR: Using an inner multi-bucket aggregation (top_hits with size: 1) inside an outer multi-bucket aggregation, is it possible to sort the buckets of the outer aggregation by the data in the inner buckets?
I have the following index mappings
{
"parent": {
"properties": {
"children": {
"type": "nested",
"properties": {
"child_id": { "type": "keyword" }
}
}
}
}
}
and each child (in data) has also the properties last_modified: Date and other_property: String.
I need to fetch a list of children (of all the parents but without the parents), but only the one with the latest last_modified per each child_id. Then I need to sort and paginate those results to return manageable amounts of data.
I'm able to get the data and paginate over it with a combination of nested, terms, top_hits, and bucket_sort aggregations (and also get the total count with cardinality)
{
"query": {
"match_all": {}
},
"size": 0,
"aggs": {
"children": {
"nested": {
"path": "children"
},
"aggs": {
"totalCount": {
"cardinality": {
"field": "children.child_id"
}
},
"oneChildPerId": {
"terms": {
"field": "children.child_id",
"order": { "_term": "asc" },
"size": 1000000
},
"aggs": {
"lastModified": {
"top_hits": {
"_source": [
"children.other_property"
],
"sort": {
"children.last_modified": {
"order": "desc"
}
},
"size": 1
}
},
"paginate": {
"bucket_sort": {
"from": 36,
"size": 3
}
}
}
}
}
}
}
}
but after more than a solid day of going through the docs and experimenting, I seem to be no closer to figuring out, how to sort the buckets of my oneChildPerId aggregation by the other_property of that single child retrieved by lastModified aggregation.
Is there a way to sort a multi-bucket aggregation by results in a nested multi-bucket aggregation?
What I've tried:
I thought I could use bucket_sort for that too, but apparently its sort can only be used with paths containing other single-bucket aggregations and ending in a metic one.
I've tried to find a way to somehow transform the 1-result multi-bucket of lastModified into a single-bucket, but haven't found any.
I'm using ElasticSearch 6.8.6 (the bucket_sort and similar tools weren't available in ES 5.x and older).
I had the same problem. I needed a terms aggregation with a nested top_hits, and want to sort by a specific field inside the nested aggregation.
Not sure how performant my solution is, but the desired behaviour can be achieved with a single-value metric aggregation on the same level as the top_hits. Then you can sort by this new aggregation in the terms aggregation with the order field.
Here an example:
POST books/_doc
{ "genre": "action", "title": "bookA", "pages": 200 }
POST books/_doc
{ "genre": "action", "title": "bookB", "pages": 35 }
POST books/_doc
{ "genre": "action", "title": "bookC", "pages": 170 }
POST books/_doc
{ "genre": "comedy", "title": "bookD", "pages": 80 }
POST books/_doc
{ "genre": "comedy", "title": "bookE", "pages": 90 }
GET books/_search
{
"size": 0,
"aggs": {
"by_genre": {
"terms": {
"field": "genre.keyword",
"order": {"max_pages": "asc"}
},
"aggs": {
"top_book": {
"top_hits": {
"size": 1,
"sort": [{"pages": {"order": "desc"}}]
}
},
"max_pages": {"max": {"field": "pages"}}
}
}
}
}
by_genre has the order field which sorts by a sub aggregation called max_pages. max_pages has only been added for this purpose. It creates a single-value metric by which the order is able to sort by.
Query above returns (I've shortened the output for clarity):
{ "genre" : "comedy", "title" : "bookE", "pages" : 90 }
{ "genre" : "action", "title" : "bookA", "pages" : 200 }
If you change "order": {"max_pages": "asc"} to "order": {"max_pages": "desc"}, the output becomes:
{ "genre" : "action", "title" : "bookA", "pages" : 200 }
{ "genre" : "comedy", "title" : "bookE", "pages" : 90 }
The type of the max_pages aggregation can be changed as needed , as long as it is a single-value metic aggregation (e.g. sum, avg, etc)
I have a web crawler that collects data and stores snapshots several times a day. My query has some aggregations that group the snapshots together per day and return the last snapshot of each day using top_hits.
The documents look like this:
"_source": {
"taken_at": "2016-02-01T11:27:09.184-03:00",
... ,
"my_metric": 113
}
I'd like to be able to calculate the derivative of a certain metric, say my_metric, of the documents returned by top_hits (i.e., the derivative of the last snapshots of each day's my_metric).
Here's what I have so far:
{
"aggs": {
"filtered_snapshots": {
"filter": {
// ...
},
"aggs" : {
"grouped_data": {
"date_histogram": {
"field": "taken_at",
"interval": "day",
"format": "YYYY-MM-dd",
"order": { "_key" : "asc" }
},
"aggs": {
"resource_by_date": {
"terms": { "field": "remote_id" },
"aggs": {
"latest_snapshots": {
"top_hits": {
"sort": { "taken_at": { "order": "asc" }},
"size" : 1
}
}
}
},
"my_metric_deriv": {
"derivative": {
"buckets_path": "resource_by_date>latest_snapshots>my_metric"
}
}
}
}
}
}
}
}
I get a "No aggregation [my_metric] found for path ..." error with the query above.
Am I using a wrong bucket_path? I've read through the bucket_path and the derivative documentation and haven't found much that could help.
The documentation mentions briefly "deep metrics", stating that they can be limited in some ways, which I couldn't quite understand. I'm not sure how or if the limitations affect my case.
We have an index named "machines", and have types "auto, bike, car, flight" in ElasticSearch
I want to get the similar brands from my search on an index - from every type
How do I query to get the top 1 document of each type, from a search on an index (having multiple types) via the Elasticsearch REST API?
Try this, using top_hits aggregation:
GET /machines/_search?search_type=count
{
"query": {
"match_all": {} //your query here
},
"aggs": {
"top-types": {
"terms": {
"field": "_type"
},
"aggs": {
"top_docs": {
"top_hits": {
"sort": [
{
"_score": {
"order": "desc"
}
}
],
"size": 1
}
}
}
}
}
}
All my documents have a uid field with an ID that links the document to a user. There are multiple documents with the same uid.
I want to perform a search over all the documents returning only the highest scoring document per unique uid.
The query selecting the relevant documents is a simple multi_match query.
You need a top_hits aggregation.
And for your specific case:
{
"query": {
"multi_match": {
...
}
},
"aggs": {
"top-uids": {
"terms": {
"field": "uid"
},
"aggs": {
"top_uids_hits": {
"top_hits": {
"sort": [
{
"_score": {
"order": "desc"
}
}
],
"size": 1
}
}
}
}
}
}
The query above does perform your multi_match query and aggregates the results based on uid. For each uid bucket it returns only one result, but after all the documents in the bucket were sorted based on _score in descendant order.
In ElasticSearch 5.3 they added support for field collapsing. You should be able to do something like:
GET /_search
{
"query": {
"multi_match" : {
"query": "this is a test",
"fields": [ "subject", "message", "uid" ]
}
},
"collapse" : {
"field" : "uid"
},
"size": 20,
"from": 100
}
The benefit of using field collapsing instead of a top hits aggregation is that you can use pagination with field collapsing.
I'm having trouble getting the sum of a nested field in Elasticsearch using a date_histogram, and I'm hoping somebody can lend me a hand.
I have a mapping that looks like this:
"client" : {
// various irrelevant stuff here...
"associated_transactions" : {
"type" : "nested",
"include_in_parent" : true,
"properties" : {
"amount" : {
"type" : "double"
},
"effective_at" : {
"type" : "date",
"format" : "dateOptionalTime"
}
}
}
}
I'm trying to get a date_histogram that shows total revenue by month across all clients--i.e. a time series showing the sum associated_transactions.amount in a histogram determined by associated_transactions.effective_date. I tried running this query:
{
"query": {
// ...
},
"aggregations": {
"revenue": {
"date_histogram": {
"interval": "month",
"min_doc_count": 0,
"field": "associated_transactions.effective_at"
},
"aggs": {
"monthly_revenue": {
"sum": {
"field": "associated_transactions.amount"
}
}
}
}
}
}
But the sum it's giving me isn't right. It seems that what ES is doing is finding all clients who have any transaction in a given month, then summing all of the transactions (from any time) for those clients. That is, it's a sum of the amount spent in the lifetime of a client who made a purchase in a given month, not the sum of purchases in a given month.
Is there any way to get the data I'm looking for, or is this a limitation in how ES handles nested fields?
Thanks very much in advance for your help!
David
Try this?
{
"query": {
// ...
},
"aggregations": {
"revenue": {
"date_histogram": {
"interval": "month",
"min_doc_count": 0,
"field": "associated_transactions.effective_at"
"aggs": {
"monthly_revenue": {
"sum": {
"field": "associated_transactions.amount"
}
}
}
}
}
}
}
i.e. move the "aggs" key into the "date_histogram" field.
I stumbled upon this question while trying to solve similar problem with my implementation of ES.
It seems that currently Elasticsearch looks at position of aggregation in the JSON body request tree - not inheritance of its objects and filelds. So you should not put your sum aggregation "inside" "date_histogram", but place it outside on the same JSON tree level.
This worked for me:
{
"size": 0,
"aggs": {
"histogram_aggregation": {
"date_histogram": {
"field": "date_vield",
"calendar_interval": "day"
},
"aggs": {
"views": {
"sum": {
"field": "the_vield_i_want_to_sum"
}
}
}
}
},
"query": {
#some query
}
OP made mistake of placing his sum aggregation inside date histogram aggregation.